These appeals against the Assessor’s valuations of 61 timeshare units at Coylumbridge, Aviemore, at the general revaluation of 2005 were referred to the Tribunal under Section 1(3A) of the Lands Tribunal Act 1949 as amended. There is no dispute that each unit is a separate unit of valuation in the rateable occupation of the timeshare owners as a group (including, in relation to unsold weeks, the developer). The main issue is whether they should be valued, as the appellants contend, under the scheme applicable to self-catering accommodation, or, as the Assessor contends, under a scheme of valuation of timeshare units which is based on dwellinghouse rental evidence. The Assessor founds on the decisions of the Lands Valuation Appeal Court in Forest Hills Trossachs Club v Central Assessor and Assessor for Highland and Western Isles v Barratt International Resorts Limited which decided in favour of dwellinghouse comparison. The appellants, however, contend that those decisions were based on the fact, or at least the assumption, that the timeshare owners themselves occupied the units for their timeshare weeks. They maintain that evidence which has subsequently been gathered materially changes the position and demonstrates that the comparison should be with self-catering units. There are additional minor valuation issues.
 On the main dispute, the Tribunal has decided that all the subjects of appeal were correctly valued in comparison with dwellinghouses and that the appeals fail.
 On the valuation issues, the Tribunal firstly upholds the Assessor’s position in relation to values under the timeshare scheme, i.e. we have decided that no deduction from the values arrived at under that scheme for Units 1 to 16 at the subjects of appeal should be made. Secondly, however, we have decided that, in the event of our having upheld the appeal on the main issue, so that the subjects require to be valued under the self-catering scheme, we would have upheld the appellants’ position on each of the two issues raised, i.e. we would have categorized Units 1 to 16 as ‘C2’ in that scheme and we would not have made the addition of 15% in respect of all the units proposed by the Assessor.
 This is the third occasion on which the issue of the correct approach to the valuation of timeshare units has been before the Tribunal. The first case, in relation to timeshare lodges at Forest Hills, concerned the 1985 revaluation, which preceded the removal of domestic subjects from the rating system. The Assessor valued the units together as a unum quid. The Tribunal upheld that approach. The court, however, upheld the ratepayers’ contentions that the units of occupancy were the individual lodges, the occupiers were the timeshare owners as a group and the lodges should be valued by comparison with dwellinghouses (Forest Hills Trossachs Club v Central Assessor, “the Forest Hills case”).
 Under the Community Charge regime, timeshare units were deleted from the valuation roll. Under the Council Tax regime, however, they require again to be entered in the valuation roll. The second case, in relation to timeshare units at Dalfaber, Aviemore, resulted from the implementation of the Local Government Finance Act 1992, which introduced the Council Tax. The Council Tax (Dwellings) (Scotland) Regulations 1993 varied the definition of ‘dwelling’ to exclude timeshare units (as defined in the Timeshare Act 1992). The factual situation in this second case was not materially different from that in Forest Hills. The Tribunal upheld the ratepayers’ contention to the effect that the result of these regulations was that the units should not be compared with dwellinghouses and that they should now be valued by comparison with self-catering accommodation (which was also excluded by regulation from the definition of ‘dwellings’). The court, however, held that dwellinghouses were a broad category of subjects which could still be recognised for valuation purposes, and that timeshare units had the characteristics and were occupied and used as dwellinghouses: they should therefore, as the Assessor contended, be valued in comparison with dwellinghouses (Assessor for Highland and Western Isles v Barratt International Resorts Limited, “the Dalfaber case”).
 In the present case, the appellants, relying on further evidence in relation to the pattern of occupancy of the timeshare units at Coylumbridge, together with their submission as to the basis of the court’s earlier decisions, are advancing again the position, upheld in the Dalfaber case by the Tribunal but rejected by the court, that the units should be valued in comparison with self-catering accommodation.
 It is agreed that the occupiers of the units are the timeshare owners, including Hilton International Grand Vacations Company (“the Company”) in respect of unsold timeshare weeks, as a group. The appeals are taken on the owners’ behalf by the trustees for the Coylumbridge Highland Lodges Club, of which the owners, including the Company, are members by virtue of their timeshare ownerships. Although the appeals are in respect of all the units, raise the same main issue and were heard together, they relate to each individual unit: evidential differences, particularly in relation to the pattern of occupation of units in the most recently developed phase of units, might lead to varying outcomes.
 Subject to the minor valuation issues, parties are agreed that if the appellants succeed, in relation to all or any of the units, the units should be valued under Scottish Assessors Association Practice Note 19, ‘Valuation of Self Catering Accommodation’ (“the self-catering scheme”); and if the appellants fail, the units should be valued under Practice Note 33, ‘Valuation of Timeshare Subjects’ (“the timeshare scheme”), which produces substantially higher values.
 If the units are correctly valued under the timeshare scheme, the appellants contend for a 20% reduction for 16 chalets in the initial phase, constructed around 1981, to reflect their inferior quality.
 If, however, the units are valued under the self-catering scheme, the appellants contend that the same 16 units should be in the accommodation category ‘C2’ in that scheme (£275 per bed space), whereas the Assessor would contend for ‘C1’ (£345 per bed space); and the appellants also oppose a proposal by the Assessor to add 15% in respect of ‘on-site facilities’ to all the values.
 The appeals were heard together on 17 to 20 November 2009. The appellants were represented by Mr MacIver, Advocate, instructed by Messrs Eric Young & Co., Chartered Surveyors. He called Michael Coletta, Finance Director, Hilton International Grand Vacations Company, Leslie Ewan, Consultant, Messrs Eric Young & Co., and James G. Honeyman MRICS, an Associate of Messrs D.M. Hall, Chartered Surveyors, to give oral evidence. The Assessor was represented by Mr Doherty QC, instructed by the Assessor for the Highland and Western Isles Valuation Joint Board. He called the Assessor, Douglas J. Gillespie FRICS, to give oral evidence. The parties lodged documentary productions. The Tribunal subsequently carried out a site inspection at the subjects (including internal inspection of one unit in each of Phases 1, 2 and 7 there) and certain other subjects in the Aviemore area (including internal inspection of a ‘Chalet Lodge’ at Dalfaber, Aviemore).
British Transport Commission v Assessor for Glasgow 1953 SC 234
Assessor for Moray and Nairn v Elgin High Church 1962 SC 524
Assessor for Stirlingshire v Myles and Binnie 1962 SC 530
Assessor for Dundee v Sisters of St Vincent de Paul  RA 515 (LVAC)
Forest Hills Trossachs Club v Assessor for Central Region 1991 SLT (Lands Tr) 42; 1992 SLT 295 (LVAC)
Barratt International Resorts Limited and Ors v Assessor for Highland and Western Isles LTS/VA/1994/4, 5.8.1996
Assessor for Highland and Western Isles v Barratt International Resorts Limited 1997 SC 384 (LVAC)
Guthrie v Assessor for Highland and Western Isles 1995 SC 594
Woodrow v Lothian Region Assessor 2002 SC 530
Spudulike Group Limited v Assessor for Tayside Valuation Joint Board  RA 91 (LTS)
Armour on Valuation, 5th Ed’n, 17-07A, 18-05 onwards, 20-45A
 On the basis of the oral and documentary evidence, parties’ submissions and our own site inspection, we find the following material facts established.
 General Description. The subjects comprise 61 units of self-catering holiday accommodation whose ownership is on the timeshare basis. They are located within the extensive woodland grounds of a hotel and leisure resort at Coylumbridge, Aviemore, in an area of outstanding natural beauty which has become a recognised and accessible year-round holiday location. They were developed in seven phases, between 1981 and 2000, and are attractively laid out in woodland areas. Generally, they are superior custom-built, fitted out and well maintained self-catering units in the ‘A’ frame style, although the design and standard has been modified and improved over the years. Units 1 to 16, Phase 1, are of timber construction. All the later phases are also mainly of timber construction but have brick or block gable walls and also provide substantially larger accommodation areas and provide individual parking spaces at each unit.
 The Coylumbridge resort comprises, in addition to the timeshare units and their reception offices, a hotel, swimming pools, solarium, funhouse, ten pin bowling, adventure playground, a staff accommodation building and various food and beverage outlets, all valued separately from the timeshare units.
 The seven phases of timeshare units at Coylumbridge are summarized as follows:-
|Phase 1||1981||Units 1-16||81.1 m2||Detached timber (‘Alpine)|
|Phase 2||1983||Units 17-26||130.63 m2||Semi-detached brick/block (‘Cairngorm’)|
|Phase 3||1985||Units 27-34||130.63 m2||Semi-detached brick/block (‘Druie’)|
|Phase 4||1987||Units 35-39||135.22 m2||Detached brick/block (‘Lochan Linn’)|
|Phase 5||1989||Units 40-45||135/129 m2||Detached/semi-detached (‘Pine’/‘Heather’)|
|Phase 6||1996||Units 46-51||135/129 m2||Detached/semi-detached (‘Pine’/‘Heather’)|
|Phase 7||2000||Units 52-61||136/149/158 m2||Semi-detached (2/3 beds.)/Detached (‘Pine’/‘Heather’)|
 Timeshare Ownership. As under other similar schemes in Scotland, timeshare ownership involves the purchase of a right to occupy in perpetuity a particular holiday unit during a specific week or weeks in each year. Once the unit is ready for sale and occupation on that basis, the developer, as “founder member”, transfers title to trustees for a non-profitmaking members’ club the members of which are the individual timeshare owners including the developer as owner of unsold weeks. The developer or residual owner then has, in respect of the units remaining unsold, the same rights as the individual timeshare owners. Each timeshare owner agrees to be bound by the constitution and rules of the club.
 The Founder Member of the Coylumbridge Highland Lodges Club (“the Club”) was the Reo Stakis Organisation, which owned the resort when the first timeshare units were developed. The hotel is now owned by Hilton Hotels and the timeshare operation by Hilton International Grand Vacations Company (“the Company”). The Company is a member of the Club by virtue of its ownership of unsold timeshare weeks. All the self-catering units at the Coylumbridge resort are within the timeshare system. The Club, through a Committee appointed by the members, employs the Company as a management company to carry out operational activities including housekeeping, maintenance and repair, and general administration of the units. The Company, which has a small office and reception facility at the resort, receives a commercial fee for these services. Members, including the company, are liable for maintenance fees, to cover these services and other outlays including rates, in respect of each week owned.
 Provided their fees are fully paid up, members may use their timeshare ownership in any year in a number of different ways. They may simply themselves physically occupy; they may gift their week to family or friends; they may let their week either privately or through a rental agent (which might be the Company or some other agent); or they may exchange their week, usually through membership of an exchange company. Hilton operate an exchange company. Exchange companies offer a wide variety of options based on the timeshare owner exchanging their own week for some other holiday facility of one kind or another, often on some form of ‘points’ basis. These points can be applied to accommodation at other resorts or sometimes to the provision of other holiday services such as flights or car hire.
 Two weeks in each year are held back as maintenance weeks. In some units, another week is used to extend the time of Christmas and New Year weeks. In 2004, this left approximately 3016 weeks as total available weeks and the maximum possible number of memberships. The Company currently still owns around 103 of those weeks. An extra week available at each unit once every 5 years is made available by the Club to the Company at a discounted maintenance fee. The Company intends to sell all the available timeshare weeks. However, the process of selling might last several years, leaving the Company with unsold units for substantial periods. The Company would anticipate a period of 5 to 7 years to sell off the weeks. As at 1 January 2005, the Company owned about 269 unsold weeks, almost all in Phase 7, which had been completed in 2000 and which took somewhat longer than anticipated to be sold. In the case of Phase 7, around 20% of the weeks remained unsold at the end of 2008. Very occasionally, individual timeshare ownerships are forfeited in terms of the constitution.
 The Company operates a substantial holiday letting business, with separate brochures and publicity, at Coylumbridge and other resorts, on the basis of making available all unsold weeks as well as offering weeks for let on behalf of individual timeshare owners. Some 60% to 70% occupancy of the unsold weeks is achieved this way.
 Physical Occupation. The actual mode of physical occupation is similar however the timeshare owner uses the week. The managers require to know who (if anyone) is coming to the unit. They prepare the unit, by cleaning and appropriate heating, for a late afternoon arrival. The unit is vacated in the morning, normally seven days later. All necessary furniture and equipment is supplied. Problems arising during the week are attended to by the Company. The Club’s rules prescribe the maximum number of occupants. Individual timeshare owners do not keep any personal belongings at the units outwith their weeks.
 Under arrangements agreed with the hotel operators, individual timeshare owners themselves staying at the units have the option of paying a weekly charge for use of the paying leisure facilities at the resort. Those renting or exchanging do not have the same option but are required to pay this fee. The public bars, restaurants, etc. in the hotel are available to everyone staying at the units.
 Use Analysis. For the year ending 31 December 2004, actual use of the weeks (other than Maintenance weeks) was approximately as follows:-
|“Owners Weeks”||“Owners Lets”||Exchanges||“Hilton Lets”|
|Phase 1 (16 units; 795 available weeks)||52%||13%||34%||1%|
|Phase 2 (10; 495)||52%||18%||29%||1%|
|Phase 3 (8; 398)||63%||13%||23.75%||0.25%|
|Phase 4 (5; 245)||56%||14%||27%||3%|
|Phase 5 (6; 295)||61%||10%||24%||5%|
|Phase 6 (6; 295)||64%||12%||17%||7%|
|Phase 7 (10; 493)||46%||4%||6%||44%|
|Total (61; 3016)||55%||12%||24%||9%|
 “Owners Weeks” were weeks in which the individual timeshare owners themselves actually used the units (“self-use”). “Owners Lets” included weeks in which individual timeshare owners let out their weeks or allowed others to use them without payment. “Hilton Lets” were unsold weeks as at 31 December 2004, available under the Company’s holiday letting business. A trend of slightly reducing “self-use” with increasing number of years of ownership, and corresponding slight increase in the total of “Owners Lets” and exchanges, can be discerned.
 Valuation Schemes. In the revaluation of 2005, Assessors applied the S.A.A. Commercial Properties Committee Practice Note 33, ‘Valuation of Timeshare Subjects’ (“the timeshare scheme”). As at the two previous revaluations, this is a scheme based on comparison with subjects used and occupied as dwellinghouses. The scheme is in two parts. A basic rate, set at £36 per m2 but now agreed at £34, was arrived at by analysis of rental evidence for houses in Aviemore. This produced a ‘lamp post’ level of value for timeshare units at Dalfaber, Aviemore. A table of comparative locational adjustment factors at a list of 18 timeshare locations in Scotland is applied. Dalfaber and Coylumbridge are each at 1.00, i.e. the basic area rate is applied with no location adjustment. The Scandinavian Village, Aviemore, is at 0.90. Lochanhully at Carrbridge is at 0.80. The other locations range from 0.85, at Loch Rannoch, to 1.20 at Cameron House, Loch Lomond, and Gleneagles. There was provision for altering the locational multipliers upwards or downwards in the case of new units built on timeshare complexes and considered superior or inferior.
 A similar appeal in respect of timeshare units at one other location, Craigendarroch, also a Hilton resort, is outstanding. All the other timeshare valuations, following the Assessors’ scheme, have been agreed. These include those at Dalfaber, Lochanhully and Forest Hills, where the company involved is now Macdonald Resorts Limited, who were professionally represented in the discussion and resolution of appeals. Detailed information, of the type produced by the present appellants, on the actual occupancy of the timeshare units at these locations, had not been obtained.
 Self-catering accommodation is also entered in the valuation roll if it falls within the definition in Schedule 2, paragraph 2, of the Council Tax (Dwellings and Part Residential Subjects) (Scotland) Regulations 1992, in summary if it is not the sole or main residence of any person and if it is made available for letting on a commercial basis with a view to profit as self-catering accommodation for short periods amounting in aggregate to 140 days or more (or intended and able to be so made available). The rateable occupier is generally the owner of the property and is in effect using the property for at least that proportion of the year for the purpose of carrying on a holiday letting business.
 For such subjects, Assessors apply a scheme, again established for many years, based on analysis of receipts and expenditure, now contained in S.A.A. Commercial Properties Committee Practice Note 19, ‘Valuation of Self Catering Accommodation’ (“the self-catering scheme”). This scheme applies differing ‘bed space’ rates to 13 “structure classes” of property, of 4 basic types, viz. ‘Luxury’ (L1), Houses (H1, H2, H3 and H4, according to standard), Chalets (C1, C2, C3 and C4) and Flats (F1, F2, F3 and F4). The table of structure classes grades and comments on the standard of each class. C1 is described as “Excellent/Very Good - Modern chalet with pitched concrete tiled roof (or similar)”; C2, as “Good Chalet - Older chalet dating from the 1970’s – felt or tiled roof (or similar)”; and C3, as “Fair Chalet - Inferior chalet dating back to the 1950s or 1960s”. Six grades of location factors – ‘Superior Holiday Centre’, ‘Main Holiday Centre’, ‘Good Scenic Area’, ‘Average Rural Location’, ‘Remote Location’ and ‘Very Remote Location’ are then applied so as to determine the applicable bed space rate. The scheme further provides as follows:-
“7.0 Additions to Value
Additions to value can be made for specific on-site facilities – e.g. games rooms, swimming pools, tennis courts or boating facilities, etc. These should be reflected by way of a percentage addition to value. It is anticipated that the general range for additions will be 5% to 10% with a maximum of 25%. No addition should be made for laundry rooms nor for reception offices. Additional facilities such as shops and public houses should be valued on the basis for that class of subject and added as an additional value.”
Competing Valuations. The Assessor contended for values, ranging from £2,750 to £5,400, arrived at under the timeshare scheme by applying (with rounding) the amended area rate of £34 per m2 to all the subjects of appeal, whose agreed areas ranged from 81.1 to 158.98 m2.
 The appellants proposed one adjustment to these figures if the timeshare scheme were applied, viz. a reduction of 20% to reflect the inferior quality of Units 1 to 16, valuing these units, after rounding, at £2,200 as opposed to the Assessor’s £2,750.
 The appellants’ proposed values under the self-catering scheme, ranging from £1,100 to £2,200, were derived as follows:-
Phase 1 (Units 1-16) - C2, ‘Superior Holiday Centre’: £275 per bed space
Phases 2-7 (Units 17-61) - H1, ‘Superior Holiday Centre’: £370 per bed space.
 The Assessor’s proposed values under the self-catering scheme, from £1,575 to £2,550, were derived as follows:-
Phase 1 - C1, ‘Superior Holiday Centre’: £345 per bed space
Phases 2-7 - H1, ‘Superior Holiday Centre’: £370 per bed space, in each case with an addition of 15%.
 Units 1 to 16. Units 1 to 16 (“Alpine” lodges) at Coylumbridge, i.e. Phase 1, constructed in 1980 (4 units) and 1981 (12 units) and well maintained, are detached, with a typical timber ‘A’ frame “kit” design with timber gables. Each lodge has a steep pitched tiled roof which extends close to ground level and the kit is built off a timber “ring beam” which sits on short concrete plinths. The accommodation comprises on the ground floor an entrance vestibule, open plan lounge and dining area with a galley kitchen off. There is also a shower room and airing cupboard at ground level. A stairway leads to the first floor where there are two bedrooms, one with en-suite bathroom. The agreed floor area is 81.10 m2, around 60% of the agreed areas of all the later units. The lodges are sited within the pine forest. The quality of fitting out of these lodges is rather lower than the more modern units, for example Phase 7, which appear generally more spacious and luxurious, but not substantially different from, for example, Phase 2.
 The Company’s holiday rental rates for Units 1 to 16 are discounted by 20%, and for Units 17 to 45 by 10%, from the rates for the newer units. This is attributed to the smaller size of the earlier lodges and some differences in lodge amenities.
 In 2008, one exchange company split the grading which it applied to the Coylumbridge resort, separating Phase 1 as a reflection of a perceived lower quality of Units 1 to 16.
 Phase 1 of the Dalfaber development comprised 33 detached timber “Swiss style” single storey chalet lodges. These were built about 1980 but have subsequently been refurbished with a glazed conservatory added. The accommodation comprises living room with dining area, 2 bedrooms and bathroom. The floor area is 52.3 m2. These lodges are sited and spaced within an open parkland setting with golf courses nearby. The agreed values under the timeshare scheme, £1,775, do not reflect any reduction of the rate of £34 per m2. Although more compact, they are comparable with Phase 1 at Coylumbridge.
 Other Timeshare Locations. The timeshare development at Dalfaber, Aviemore, is comparable with the Coylumbridge resort although the setting has a different character. It is located in a landscaped area on the bank of the River Spey, at a similar distance from the village of Aviemore, and with an attractive open outlook to the surrounding hills as opposed to the woodland setting at Coylumbridge. The site includes in addition to the holiday units a country club with bar, restaurant, swimming pool and games hall, and (now) two golf courses. There is no hotel on the site. The units are attractively laid out although of more varied style than those at Coylumbridge. The resort has the same agreed location factor, under the timeshare scheme, of 1.0.
 3 self-catering units at Dalfaber, of the ‘Cairngorm’ type, constructed as timeshare units and identical to some timeshare units built at the same time, had in fact not been put onto the timeshare basis and were retained by Macdonald as self-catering holiday rental units. The Assessor accepted that these required to be valued on the self-catering basis, resulting in agreed values of £1,500, with no addition to the applicable bed space rate of £370. No percentage addition comparable to the 15% proposed by the Assessor if the self-catering scheme applies at Coylumbridge was made. Identical, neighbouring units had agreed values under the timeshare scheme of £4,600.
 Lochanhully holiday resort is situated a short distance east of Carrbridge and about 7 miles from Aviemore. This timeshare development comprises mainly 1 or 2 bedroomed detached timber chalets set in an attractive woodland setting. There is a reception office and limited indoor facilities which include a children’s playroom, gymnasium, swimming pool and sauna. The agreed location adjustment factor, under the timeshare scheme, of 0.80 reflects the greater density of this chalet development, the more limited facilities and the distance from Aviemore and other attractions.
 The Scandinavian Village is a timeshare development situated close to the centre of Aviemore. It comprises 66 homes, mainly linked villas and flatted villas. In January 2005 the surrounding area, which is understood now to be scheduled for redevelopment as part of the regeneration of the Aviemore Centre, was in a transitional state, with no on-site facilities although close to the village and other attractions. The agreed location adjustment factor of 0.90 reflects the nature of the accommodation and its immediate surroundings at the valuation date.
 Both Mr Ewan for the appellants and Mr Gillespie, the Assessor, are very experienced rating surveyors who have had substantial ongoing involvement in the issue of timeshare valuations.
 Mr Ewan said that it was essential to understand the history of the legislation and the cases setting down the criteria for valuation of this unusual genus of subject, and an understanding of what timeshare was about would also be invaluable. He took from the Forest Hills case that the question whether the units were dwelling-houses for valuation purposes must be answered by looking at the whole facts and circumstances and that the physical characteristics of the properties would not be sufficient to identify them as dwellinghouses. It was important to look at what was happening throughout the year and at the use to which the property was devoted as well as the rights of the occupiers. The absence of conflicting or different uses, as well as the absence of ‘rival’ occupiers, at Forest Hills had been highly significant. The court had expressed a critical reservation if the subjects had been let for profit over parts of a year. The court had been satisfied that the units were places where people lived, throughout the year, albeit each certificate holder only lived there for a short period each year. This was an exercise of permanent rights. In the Dalfaber case, the Tribunal had found that the units had the characteristics of dwellinghouses and the court held that there was a fundamental difference of use between self-catering accommodation, where the landlord was in occupation and using the subjects commercially, and timeshare units, where the (successive) holidaymakers were the occupiers and using the subjects for the purposes of a dwellinghouse. In the present case, Mr Ewan said, the evidence showed that the timeshare owners were no longer in successive occupation: others occupied for substantial portions of the year. There was sufficient ‘rival’ occupancy to raise the question whether comparison with dwellinghouses was still appropriate. Timeshare, or interval ownership, would be looked at in detail to show the interrelationship and why the holiday rentals market was the most direct form of competition for the timeshare industry and therefore the most appropriate comparison.
 Mr Ewan then looked at timeshare. It was necessary to understand its direct links and competition within the leisure holiday market. The actual use and occupation of the subjects of appeal would establish an alignment with the general use of short term holiday accommodation units. He reviewed the different holiday ownership structures. There were two types of timeshare structure, ‘deeded property ownership’, where ownership units were divided into weeks, and ‘right to use’, where units might be divided into weeks or intervals with varying numbers of points which could be exchanged. The fixed week structure ensured a holiday in a specific period and gave the option of exchanging that interest for another resort at another season. Floating weeks, points clubs and ‘banking’ all arose, a key feature being the ability to exchange. The timeshare week could be offered as a holiday rental. Timeshare and its derivatives were basically in competition with other forms of holiday lodging, the most direct competition arguably being from holiday rentals. The leading timeshare exchange company, along with others, was also in the holiday rentals business.
 Mr Ewan explored the exchange feature further. Exchange mechanisms were more complex than a simple swap which may have been the perception in the past, systems having developed as timeshare had become fully integrated into the holiday accommodation market place. The timeshare week was ‘banked’, giving ‘trading power’ ranked on criteria such as location, resort quality, etc. Exchange membership was restricted to owners at resorts affiliated to particular networks, with options to join other exchange companies and ‘double trade’. There was a market place in which exchanges were another form of holiday rental, no different, Mr Ewan argued, from offering a second home for let for parts of the year.
 Mr Ewan explained that after the Dalfaber case, in which it had been inferred that there was an alternative use and occupation of timeshare units for holiday lets and exchanges but there had been no empirical evidence quantifying the different uses and occupation, it had been decided to collate and record such information throughout each year and over a substantial period of time, in order to establish a ‘use matrix’ and indicate whether there was sufficient alternative use and/or occupation to influence the ‘dwellinghouse’ basis. Looking at the revenue principle, and bearing in mind that a valuation usually remains on the roll for the period of the quinquennium, it was considered proper to base the value on the data for the preceding five years and therefore to reconsider the position when such data was available for the 2005 revaluation.
 Mr Ewan next described the subjects, and the timeshare operation there, in some detail.
 He then reviewed the criteria for identification of a dwellinghouse, looking at physical characteristics, use and judicial constructions in various contexts, and proposed what he described as a suitable definition for a dwellinghouse, combining physical characteristics and actual use and also considering the degree of permanent residence, as follows:-
“Fully or partially self contained accommodation (there may be some shared facilities) being a structure of a permanent nature constructed or adapted to be capable of being dwelt in by human beings and will contain or have access to at least a living room, bedroom or sleeping area, kitchen or kitchen area and bathroom providing the main activities of day to day domestic existence which is wholly occupied and used by a household privately on a permanent basis and only for such a purpose or purposes.”
 The building, he argued, had not only to provide the facilities for day-to-day domestic existence but also to be used as such. Whatever the type or form of household living there, there would have to be a degree of permanent residence over time. The short term holiday rental on a self-catering basis was a use which was more akin to the use of the timeshare units at Coylumbridge rather than the exclusive venue. According to HM Revenue and Customs criteria for a ‘furnished holiday letting’, it must be available to let on a commercial basis for at least 140 days, let for at least 70 days and not occupied by the same individual for more than 31 consecutive days for at least 7 months of the year. These criteria appeared to have influenced the exclusion of self-catering accommodation from the definition of ‘dwelling’ for Council Tax purposes. It would therefore be reasonable to assume that in other circumstances it was left to the Assessor’s judgment as to whether there was a sufficient commercial use to distinguish it from that of a ‘dwelling’ for Council Tax purposes.
 Mr Ewan contended that the owners remained as rateable occupiers because cumulatively they alone met the criteria of permanent and paramount use in the rating sense, third party occupancy for short term holiday accommodation being a transitory occupation, as at self catering units. Lands and heritages should be valued in their actual physical state and according to their use and occupation, not on the basis of some other more profitable use.
 Mr Ewan then introduced his analysis of the use of each timeshare unit. In relation to exchanges, there was no open currency changing hands as in a conventional holiday let but exchanges were another form of holiday rental available to the timeshare owner who in return could purchase an alternative holiday package using the ownership value as collateral. Once the owner made the decision to exchange he forfeited his right to occupy, which passed to the exchange company. Occupation passed to a third party for short term holiday accommodation. If it was probably just another timeshare owner occupying, that was not relevant. It was his considered opinion that due to the complex arrangements involving the exchange mechanisms and the implied bartering or trading involved it was legitimate to include all the exchange transactions as equivalent, or at least similar, to traditional holiday rental. The important point was that the timeshare owner no longer occupied the specified lodge when an exchange mechanism had been triggered. The analysis of the lodge use at Coylumbridge had produced figures for third party occupation which in his opinion questioned the view held by the outcome of the Forest Hills and Dalfaber cases that the use of the various timeshare units was as dwellinghouses due to their being successively occupied by the owners. There was substantial occupation by third parties for short intermittent use as holiday accommodation. Such a volume of occupation and use did not accord with the interpretation of such accommodation as a dwellinghouse.
 Mr Gillespie’s evidence on the main issue can be summarized more briefly. The Lands Valuation Appeal Court had made clear that timeshare subjects and self-catering subjects were different categories of subjects for the purpose of valuation for rating. The subjects were dwellinghouses and required to be valued by comparison with dwellinghouse rents. The rateable occupiers were not using the lodges to carry on the business of letting of self-catering subjects. These decisions were clear and binding. Although there was substantially more evidence now, the facts did not appear to be materially different from the facts considered in the Dalfaber case, and broadly the same issue had been considered. He referred to Finding 23 in the Dalfaber stated case.
 Overall, said Mr Gillespie, whichever period was taken, more than half of the available weeks were used personally by the timeshare owners, so that even if that was the only use as a dwellinghouse, it was still the principal and characteristic use of the subjects. The number of unsold weeks across the resort in 2005 was the same as in the Dalfaber case. Phase 7 had substantially more (although still less than half), but that was reducing. Accepting that the Company had the rights of a timeshare owner, it clearly wished some return, but the intention and hope was that the period during which it had unsold weeks would be short lived.
 In Mr Gillespie’s opinion, it was incorrect to treat exchanges and owner lets as not being dwellinghouse uses. Timeshare owners were consumers. According to a United Nations discussion paper, few if any purchased with a focus on the generation of rental income. Although some exercised the option to exchange, that was not as a business venture. Letting by some owners was also consistent with dwellinghouse use and different in character from the occupation by a self catering operator. Profit was seldom likely to be made. Ordinary dwellinghouses might be let, and/or exchanged with other dwellinghouses, for significant periods in a year, consistent with dwellinghouse use. In addition to personal occupation by the timeshare owners, exchanges and letting were in the circumstances reasonably regarded as uses by the rateable occupiers – the timeshare owners as a whole – which were dwellinghouse uses or uses ancillary or incidental to use as a dwellinghouse. Neither was a rival use.
 Mr Gillespie also pointed out that since the Dalfaber case there had been almost universal acceptance that timeshares should be valued by comparison with dwellinghouses.
 Mr Gillespie looked, with the assistance of the appellants’ data as well as his own interpretation of that, at the lodges individually. Only some 7 lodges in Phases 1 to 6 had less than 50% self use by timeshare owners, none less than 44%; the timeshare owners’ lets were not commercial with a view to profit; and Hilton’s aim was to generate income until the weeks were sold. Nor were the exchange weeks commercial or with a view to profit. There was little difficulty in concluding that these 7 lodges were used as dwellinghouses. The proportion of unsold weeks was highest in Phase 7, where 5 out of 10 had less than 50% “self use”, but even reviewing these individually, the same result was reached, considering exchanges and unsold weeks not actually let.
 Mr Gillespie added that the differences between the two levels of value were not surprising, given the different uses. One was use by an end user, a consumer; the other, use by a business operator. Again, dwellinghouse use occupancy would be about 90% to 95%, compared to 50% to 60% at the better end of the self-catering market. In answer to questions by the Tribunal, in relation to the situation at Dalfaber where units were intended to be sold as timeshare units when the market was right but meantime used on the self-catering basis, Mr Gillespie said that when one timeshare week was sold, the property passed to trustees for the timeshare owners, the change was triggered and the rateable occupier became the collective person. Hilton’s primary purpose in relation to the unsold units was to sell. Meantime, they were simply minimizing their loss by recouping something towards their expenses.
 In his submission on the appellants’ behalf, Mr MacIver started by reviewing the context and basis of the appellants’ case, as explained by Mr Ewan. It was their submission that the court’s decision in the previous cases had been on the basis, or at least the assumption, that the timeshare owners actually used the units for their timeshare weeks. He then reviewed all the witnesses’ evidence at some length. He submitted that when unsold weeks were offered for let, this was a straightforward letting business, carried on over a substantial period, even accepting that it was to an extent ancillary. Where an individual timeshare owner appointed the Company or another company to act for him in letting out a timeshare week, the company was acting as agent in a business of letting out property and the person actually using the unit was there as the result of a business arrangement. Looking at the owners as a group, one found quite a lot of this use. In the case of exchange, the timeshare owner joined an exchange company, paid a fee and benefited from some internal currency. In law, he appeared to assign or transfer his interest to the exchange company, even if only for a limited period or subject to revocation. Again, the exchange company was carrying on a business and the person who actually used the unit was there by virtue of a business arrangement. The timeshare owner had deposited or ‘forfeited’ his week. In relation to Mr Gillespie’s evidence about the evidence and findings in the Dalfaber case, the point was that the case had not been presented in that way. As a matter of fairness to ratepayers, it could not be right that, as at the Cairngorm chalet at Dalfaber, an identical house on one side of a dividing wall should be liable to almost three times more rates than its neighbour. Both properties might be actually let out. Mr MacIver accepted that it might be necessary to look at groups of units, e.g Phase 7, or even individual units, differently. He accepted that the factual position at Phase 7 was different. The appellants’ analysis of years 2000 to 2004 should be preferred to the Assessor’s of two years, 2003 and 2005.
 Turning to the law, Mr MacIver first referred to passages in Armour, at 18-05,09,10,11 and following, and 13, in relation to the ‘actual state’ rule. There was no issue as to potential use, or arbitrary restriction. He referred also to 17-07A and 20-45A. He reviewed the decision of the court in the Forest Hills case, particularly the references to the lack of conflicting or different uses; Lord Prosser at 297H,L, 298A-B, H-I, 299 and 300A; Lord Coulsfield at 300E, 301F-302E and, particularly, 302I, where his Lordship was considering the particular scenario in point in this appeal; and Lord Milligan at 302L-303D. He referred to the decision of the Tribunal in the Dalfaber case, at pages 6,10,11 and 14; and, in the opinions of the court, Lord Prosser at 386E-G, 387D-G, 388 (foot)-390B; Lord Gill at 391B-C, 393C, and Lord Coulsfield. There was no reference to finding-in-fact 23. Mr MacIver also referred to Assessor for Stirlingshire v Myles and Binnie; Assessor for Moray and Nairn v Elgin High Church; Spudulike Group Limited v Assessor for Tayside; Woodrow v Lothian Assessor; Assessor for Dundee v Sisters of St Vincent de Paul; British Transport Commission v Assessor for Glasgow; and Guthrie v Assessor for Highland, particularly per, Lord Clyde at 595G and 595C and Lord Milligan at 598C and following.
 Mr Doherty responded with a series of numbered submissions:-
1. ‘Dwellinghouse’ was a broad category.
2. ‘Dwellinghouse’ includes both timeshares and holiday homes.
3. Whether a subject with some dwellinghouse use and some other use remained a dwellinghouse was largely a matter of impression. Here, Mr Doherty referred extensively to the circumstances and the opinions in Guthrie.
4. Where subjects had the physical characteristics of dwellinghouses and significant dwellinghouse use, there would have to be clear and compelling evidence of a rival use of such an extent and nature as to alter the position. The timeshare units retained their character as holiday homes for the individual timeshare owners.
5. Rival use sufficient to give rise to a situation where dwellinghouse use was lost was almost always likely to be a business use by the rateable occupier.
6. The relevant existing use was the use of the rateable occupier.
7. The rateable occupiers were the body of timeshare owners, including Hilton.
8. It was not disputed that ‘self use’ was dwellinghouse use. Taking 2005 as the best evidence (the relevant date being 1 January 2005), this was 55% to 60%.
9. What was the competing, or rival, use which removed that position?
10. Letting by timeshare owners was consistent with dwellinghouse use. It was not a business nor a commercial use. The motivation, in this case, to defray losses and expenses, was relevant. In any event, the extent was not large. Again, reference was made to Guthrie.
11. As to exchanges, timeshare owners had always had this option. Obtaining an exchange was not operating a letting business or an exchange business. It was simply incidental, and not a rival or competing use, like dwellinghouse owners arranging a house swap. There was no evidence of any formal assignations. ‘Banking’ was only available in one points scheme. This lacked commercial character. The vast majority was exchange for timeshare elsewhere. This was under a quarter of the year.
12. As to the unsold weeks, the use of the units then was in one sense commercial, but the context and motive were relevant. The main aim was to sell these weeks, but the Company had running costs to meet. This was in line with the position noted by the Tribunal in the Forest Hills case, at 47H. Phase 7 skewed the picture about the extent of this: over the resort as a whole, in 2005, it was only about 7%, and only 60% to 70% actually let. This was not a compelling indication of rival use substantial enough to remove dwellinghouse character.
13. Collectively, the owners including the Company were liable throughout the year for maintenance costs, comparable to the cost of the housekeeper in Guthrie.
14. The facts were not materially different from the Dalfaber case.
15. Mr Ewan, despite having accepted that the exchanges and lets did not take the units over into business occupation and use, was asking for the subjects to be valued as if it were – the same error as in the Dalfaber case. Valuation had to be in accordance with existing use.
16. Even looking at the units individually, none had lost the character of a dwellinghouse.
17. Differences in values between dwellinghouses and self-catering units were attributable to the different uses, not by the holidaymaker but by the rateable occupier. No middle course between the two sets of values was possible. In so far as there were indications that one or other might not be so firmly based, on the evidence, it was clear that the timeshare scheme had the better basis.
 Mr Ewan considered that there had to be an adjustment between the values of the Phase 1 units and those of the remainder, to reflect what he described as pronounced physical differences. The construction was not as good and there was no individual car parking at the lodges. In relation to the timeshare scheme, he accepted that the smaller size was reflected and that the scheme was based on uniform basic rates applied across the board, but suggested that the locational adjustments reflected development quality and there could be provisions to allow for quality adjustments within developments. Values derived from main dwellinghouse stock should reflect design, construction and quality issues. The Assessor had identified a quality differential under the self-catering scheme. The 20% deduction claimed under the timeshare scheme was arrived at from the evidence that rentals had had to be discounted by 20% by comparison with the more modern and conventionally constructed units at Coylumbridge. He also relied on the evidence of different market perceptions found in RCI members’ ratings.
 In relation to the self-catering scheme, Mr Ewan argued that the overall design specification of this phase came from an earlier era, making C2 the appropriate classification, the Assessor’s C1 classification being appropriate to a chalet of superior size and specification. As to the Assessor’s proposed 15% addition for ‘on site facilities’, the other facilities, apart from the hotel adventure playground and the timeshare offices were all separately entered and accounted for. Timeshare occupiers had no special privileges for the use of adjacent facilities. No similar addition had been made in the agreed valuations of the three self-catering units at Dalfaber, or, apparently, anywhere else.
 Mr Gillespie considered that there was no basis for granting an allowance at Phase 1 under the timeshare scheme. The construction differences were not material. Relative advantages and disadvantages balanced out and the smaller size of these lodges was taken into account by valuing on an area basis, a broad approach which had been applied and accepted over several revaluations. The holiday rental tariffs differed by only 10% between Phases 1 and Phases 2 to 5. The Dalfaber chalets were valued at the same £34 rate and were poorer than the Phase 1 units. Granting the allowance would take the values down to those in the poorest timeshare resort, Lochanhully.
 Under the self-catering scheme, Mr Gillespie considered that ‘C2’ was for poorer, older chalets dating from the 1970s. These would typically be lighter and cheaper, with felt roofs. The Phase 1 chalets were of ‘C1’ rather than ‘C2’ quality. Further, without the 15% addition, the subjects would be undervalued, having regard to their location and the proximity of on-site facilities. Timeshares had significantly higher occupancy. He did not accept that the top locational factor, ‘G+’ for the Aviemore area as a “Superior Holiday Centre”, would adequately reflect the value for subjects with 90-95% occupancy, compared for example to self-catering units at Dalnabay. He accepted that he was not aware of any other similar addition, and that the self-catering scheme would apply at, for example, Gleneagles and Crieff. The failure to apply the same addition at the Dalfaber self-catering units was an error.
 In his closing submission, Mr MacIver repeated the appellants’ basic contentions as to differences under the two schemes, but did not elaborate.
 Mr Doherty’s submissions 18 and 19 on the valuation issues also did not add substantially to Mr Gillespie’s opinion evidence. He emphasized that under the timeshare scheme one rate fitted all and that was the ‘tone of the roll’. The position at Dalfaber was similar. The Phase 1 units were smaller but that was taken into account. The absence of parking had pros and cons. Even if there was some adjustment, 20% would be far too much, having regard to the rental evidence and the comparison with Lochanhully.
 In relation to the self-catering scheme, Mr Doherty again referred to the rental evidence, which did not support ‘C2’ classification alongside ‘H1’ for Phases 2 to 7. In relation to the locational increase, Mr Doherty apparently placed this at 10%, in line with the Tribunal’s decision, relating to the same scheme, in the Dalfaber case. The self-catering scheme had been prepared without reference to timeshare subjects which usually had on-site resort facilities, making adjustment appropriate. The erroneous failure to apply this addition in the three cases at Dalfaber could not be used to support the appellants’ position.
 Timeshare units may be thought to sit slightly uneasily within the system of valuation for rating of non-domestic subjects. ‘Commercial’ self-catering holiday accommodation is also entered on the valuation roll. The main issue in these appeals is whether the subjects should be valued under the established scheme applicable to such self-catering holiday accommodation or in comparison with dwellinghouses, under the established and straightforward scheme applied by the Assessor.
 Our starting point is of course the authoritative decisions by the Lands Valuation Appeal Court that timeshare units, or at least timeshare units occupied and used in what might be described as the ordinary way, i.e. by the individual timeshare owners as holiday homes for themselves (“self-use”), are used as dwellinghouses and are to be valued in comparison with dwellinghouses. However, we accept the appellants’ argument that it is legitimate to look at matters again (if the evidence justifies it), because the Forest Hills and Dalfaber cases were decided on the basis, or at least the assumption, of such “self-use”. The appellants rely on evidence about lettings, both of unsold weeks and by individual timeshare owners, and also exchanges. As to lettings by the original developer of unsold weeks, Lord Coulsfield in the Forest Hills case entered a specific caveat, at 301I, and the opinion of Lord Prosser was, we think, to similar effect, at 298I and also by implication in his discussion from 299B to 300A. In the Dalfaber case, Finding-in-Fact 23 does seem to suggest quite a substantial degree of use other than “self-use”, on one view not a lot different from the evidence now before us, but there is no indication of the caveat having been explored in that case, either in submissions or in the opinions of the Tribunal or the court. In that case the issues can be seen to have developed along different lines arising out of the provisions regulating the then new Council Tax regime. The significance of lettings by individual owners, or the exchange system, were not apparently argued and did not feature in their Lordships’ opinions. We have a degree of hesitation about these aspects, because they do seem to have been well enough known about. However, if the extent of lettings of unsold weeks raises an arguably new situation, it seems appropriate also to consider whether the whole picture of such lettings plus other situations which are not “self-use” does so. The appellants have painted a picture of a much more involved modern system of exchanges which (they argue) is significant. We conclude that we can and indeed must consider the main issue again.
 Nor do we think that we can accept Mr Doherty’s submission No. 15 as a complete answer in itself, if indeed it was intended as such. The appellants’ acceptance that the timeshare owners as a group, including the Company in respect of unsold weeks, remain the rateable occupiers, no doubt gives them an awkward starting point, but it does not, in our opinion, in itself invalidate their argument. As we understand it, they argue that there is a form of rival occupancy which throws doubt on the valuation category but is not such as to question the paramount occupancy of the timeshare owners, including the Company, as a group. This appears to us a possible approach, just as an assessor, such as the Assessor in Guthrie, does not need to identify a different rateable occupier in order to enter subjects on the valuation roll and value them under the self-catering scheme. This form of ‘rival occupancy’ argument appears to be the new issue in these appeals. The court in Forest Hillsenvisaged the possibility of such a situation, but it did not arise on the facts then considered. That case was considered on the basis that, apart from maintenance weeks, where the company’s occupancy was purely ancillary, the company retained no rights or interest. The situation in the Dalfaber case, in which the ratepayers accepted in the court that timeshare units were still dwellinghouses in terms of their use (389D-E), was the same.
 These things said, we of course recognise and must apply the court’s reasoning and guidance in so far as it relates to the factual situation in these appeals at the relevant date. In the two timeshare cases, and also in Guthrie, the court has clearly regarded holiday houses as physically dwellinghouses used solely for residential purposes. “Self-use” of these timeshare units remains part of the picture and must be regarded as dwellinghouse use. If Mr Ewan’s proposed definition of a dwellinghouse excludes “self-use”, we cannot accept that.
 Both sides referred to the court’s consideration of the circumstances in Guthrie. That does appear relevant in this case, because the subjects were a holiday house used partly for private purposes and partly for “commercial” letting. The issue was whether the subjects stayed in the (then) Community Charge regime as ‘domestic subjects’ or should be valued, presumably under the self-catering scheme, on the basis of the commercial use. ‘Domestic subjects’ were defined under reference to dwellinghouses. Although timeshare units are now anyway expressly excluded from Council Tax, and there is also now a different definition by regulation of excluded self-catering accommodation, the issue was at least similar to that in the present case. The court rejected the Committee’s approach of balancing the most valuable and less valuable periods of the year, an approach characterised by Lord Milligan, at 598E, as “the sort of clinical analysis which may be appropriate, for example, in some derating cases”. That would seem to suggest that in the present case simple mathematical comparison of “self-use” and “commercial” use is not decisive. Lord Clyde said at 597D-E:-
“… the question is one of impression in the particular facts and circumstances of the case. One starts in the present case with the solid fact that the subjects are physically a dwellinghouse, together with the fact that they are used solely for residential purposes. They do not possess the physical characteristics of a hotel or a public guest house. The only ground for claiming that they should not be classified as a dwellinghouse is said to be in their use. In my view, in the circumstances, there would have to be some clear and compelling evidence to establish that the subjects are business premises before the considerations of the physical appearance and the actual private domestic use made of them can be discarded and their entry in the roll affirmed as correct.”
 Lord Milligan also referred to the question as being whether the “character of a dwellinghouse” had been lost and to the approach of impression in the particular facts and circumstances. He continued, at 598E:-
“Account must be taken in the exercise involved in forming the impression mentioned of the physical characteristics of the subjects and the apparent motivation of the appellant in the use made of the subjects concerned albeit that objectivity is involved in assessment of such fundamentally subjective consideration.”
 The particular facts and circumstances of timeshare units may seem rather different from those in Guthrie. The court evidently considered the strength of the family’s own use, maintaining for example significant articles of furniture and paintings in the house, and the essentially private method of obtaining tenants, to be amongst the relevant considerations. The similarity of the actual physical occupation of timeshare units with occupation of purely commercial holiday self-catering units, built and functionally fitted out in the same way, a situation very different from that in Guthrie, would seem to be of at least some relevance. However, we cannot lose sight of the fact that the court has characterised timeshare units in the same basic way, i.e. as dwellinghouses.
 Matters are complicated by the unusual “successive” occupancy which the appellants accept still applies despite the addition of the Company to the group. We are not sure that we can put the picture of holidaymakers coming and going weekly out of mind, as the logic of this occupancy by the group, partly composed of a company, might suggest, but we think that we should regard the owners, both individuals and the Company, as a group. Thus where, for example, three quarters of weeks are “self-use”, we should, we think, view it as if the owner (or conceivably tenant), of a holiday home is himself actually using the house for three quarters of the year. With the assistance of Lord Prosser’s analysis in Forest Hills at 299J, we could say that the house is occupied in that way for that proportion of the year. Similarly, if there are a number of weeks of letting, we should view it on the basis that the house is let out for that number of separate weeks. Of course, an individual timeshare owner who (like most) only owns one week is only letting for one week, which might not seem of any significance, but the rateable occupier, the group, is letting for the number of weeks. Similarly with exchanges.
 We have to consider the nature of the use by the occupier, “what the subjects are used as” (again, Lord Prosser, at 299D). We accept the appellants’ statistics as accurate so far as they go, and do not rule out reliance on statistics as helpful in uncovering the true nature of the use of the subjects, but we are of the clear view that the appellants’ approach of relying on the statistics from 2000 to 2004 so as to show the position over the whole of that period is misconceived. It is true that under one valuation principle, the Revenue Principle (of which the self-catering scheme could loosely be described as one example), the principle is that past results for the whole of one period are used to fix the rental value for the next, so that they all, as it were, count. That, however, is a valuation issue. A question as to the nature of the subjects is quite different. The Assessor is required to value the subjects as he finds them on a prescribed date, in this case 1 January 2005, and if the subjects, or their use, are the subject of material change, alteration of the value to reflect that change may be required. We did not understand Mr MacIver to suggest otherwise. The search, accordingly, is not for information about the nature of the subjects covering the whole previous quinquennium, but rather about the position on the relevant date. Realistic enquiry is of course not limited to the particular day, but looks for a reasonable picture of the use of the subjects at that time.
 An additional reason in this case for rejecting figures based on the whole period, 2000 to 2004, is that they are quite clearly skewed by inclusion of the figures for Phase 7, because that phase was only completed in 1999 and almost no weeks had been sold by 2000. Sales took place over perhaps a rather longer period than the Company would have wished, but the number of unsold weeks was on a clearly declining trend. So use of the statistics for the first two or three years distorts the picture of the position at the end of the period, when the proportion of unsold weeks in Phase 7 had come down to 44%. In fairness to the appellants, they did produce the information through to the end of 2008, by which time further sales had taken place, enabling some sort of balancing of this matter, but the idea of requiring information right through to near the end of the valuation quinquennium in order to decide on the correct method of valuing the subjects for that quinquennium is also to our mind obviously inappropriate.
 Our very condensed findings, compared to the very comprehensive information provided by the appellants, have therefore been directed at giving a reasonable picture of the position as at 1 January 2005. Even at that date, Phase 7 presented a different picture from the rest of the subjects, particularly in relation to unsold weeks (but also in relation to exchanges), so it was appropriate to make findings for each phase. What we have done is to show, as percentages, the four categories of use as set out in the appellants’ production. We have also shown the percentages for the development as a whole.
 The appellants’ statistics identified the number of available weeks for each unit, either 49 or 50, after removing the two maintenance weeks, and revealed four categories of use. ‘Owners Weeks’ comprised the “self-use” which was generally under consideration, or assumed, in the Forest Hills and Dalfaber cases. ‘Owners Lets’, as we understood it, was not able to distinguish between weeks gifted by individual owners to family or friends and weeks actually let by individual owners, nor was there any information about the sort of rental levels asked or achieved by individual owners when letting otherwise than by using the Company as letting agents. ‘Exchanges’ included, again without being able to break down, both traditional exchanges of one week for another, normally at another resort, and the more sophisticated form of “trading” described by Mr Ewan. ‘Hilton Lets’ were the unsold weeks, at the relevant date mainly in Phase 7, when the units were offered by the Company for self-catering holiday letting.
 The nature of “self-use” is clear and on any view forms a substantial part of the overall impression. This is plainly a very significant part of the picture, although it is a slightly smaller part of the picture at Phase 7.
 The appellants totalled “Owners Lets”, “Exchanges” and “Hilton Lets” as “Minimum 3rd Party Occupation” and founded on the overall average for the years 2000 to 2004 inclusive. This requires us to look closely at the nature of letting and exchanges.
 In relation to unsold weeks (“Hilton Lets”), which we were told were all put into the letting system, with occupancy rates of 60% to 70%, this is in our view commercial letting of self-catering holiday units, in competition with all the variety of self-catering units valued under the self-catering system. It seems to us that the units are used in this way for all the unsold weeks, i.e. whether or not a letting is actually achieved. We note Mr Coletta’s evidence that if the Company used an unsold week for promotional purposes, this had to be accounted for to the letting business.
 The Assessor argues that this activity simply involves the Company, which is a property developer looking for a capital profit, seeking to defray some of its expense during the period before the property is all sold and the profit realised. Our impression, however, is that there is a clear business model including a separately promoted holiday letting business carried on over a large number of years, spanning the various successive phases of the development. This appears to be a separate business, which also takes in agency for the individual timeshare owners who wish to let. The letting brochure produced does not suggest anything less than a full market rent, the market being the holiday letting market. We did not specifically learn whether a “profit”, whatever that might mean in this context, was achieved by this business, but it would seem clearly to have aimed for profit, and in view of its scale and the occupancy rate achieved we find it difficult to agree with the picture which Mr Gillespie painted of simply an attempt to recoup some expenditure. Looking, at this stage of our consideration, at the character of the use of the units during the unsold weeks, we think we must follow the ‘actual state’ rule, that subjects must be valued in their actual state and according to the actual use to which they are devoted. The Company’s use of the unsold weeks at Coylumbridge is similar in many ways to the use made by Macdonald Resorts of three of the units at Dalfaber which they no doubt also aim to sell but meantime use entirely for lettings. Other situations might be envisaged in which an owner trying to sell property meantime makes a business use of it. If the use has a sufficient degree of permanence, as we think is the case here, the subjects should, under the ‘actual state’ rule, be assessed on the basis of such use. We think that it is at the different stage of forming the overall impression of the use by all the owners as a group that the occupier’s apparent motivation, referred to by Lord Milligan, comes in.
 This letting activity, however, only took place for some of the year. At the relevant date, we have found this to be no more than 3 weeks at any of the units in Phases 1 to 6, so that it can be said that once the timeshare units are substantially sold, as is intended and generally happens, it is like the owner of a holiday home offering it for let, on a commercial basis, for not more than 3 weeks in the year. At Phase 7, however, it was clearly at a rather higher level.
 Individual timeshare owners also sometimes let, or try to let, their weeks. It seems to us that at least some of that activity may also properly be described as commercial letting. Again, the Assessor raised the issue of the purpose or intention. He referred to a paper suggesting that few, if any, timeshare owners bought with a view to generating rental income. We can accept that, but it seems to us that it would be the intention or purpose at the relevant date which should be considered. There is a picture of ‘Owners’ Lets’ at the relevant date declining slightly through the phases, being more prevalent at the older units where the individual owners would generally have purchased rather longer ago. It seems credible that as the years following purchase go by, some timeshare owners may not wish to use the weeks so much themselves, and indeed we were told that it was not uncommon for some of the older units to lie empty some weeks. Some may have sought what would in effect be an investment income from their units rather than selling (or indeed whilst trying to sell). If, as also seems consistent with the letting brochure which makes reference to older units as well as Phase 7, owners are placing weeks with the Company for letting, that would seem to us comparable to the position in relation to unsold weeks, and similarly if they were placing their weeks in the hands of other letting agents or simply themselves advertising the weeks for let. Such activity would seem to us to belong, in the overall picture, alongside the Company’s use of unsold weeks.
 However, the exact extent of that cannot be known. Further, it would only apply to any significant extent to units in earlier phases where there was a very low incidence of unsold weeks used by the Company for their letting business.
 On exchanges, we part company with the appellants’ arguments. Again, we accept the appellants’ factual evidence, including Mr Ewan’s description, of the more sophisticated ways in which exchanges can now be used, although we were not clear as to the frequency of this as compared with ‘traditional’ exchanges of the week owned with another week at another resort. However, as we see it, the position about traditional exchanges of weeks is just the same, when properly considering the nature of the use made by the occupier, as any of these more sophisticated forms of ‘trading’ in timeshare weeks. The exchange companies are certainly carrying on a business, but the occupier, the timeshare owner, is a consumer. He has a property right which he can use by swapping, just as a dwellinghouse owner or tenant might seek to exchange his house with another. In the case of a holiday house, that might be quite frequent. Even if, under modern exchange schemes, the right is in the nature of a form of currency, it is still held by a consumer and not a business. The suggestion was made that when exchanging (and possibly also when letting) the timeshare owner was handing occupation over to another party, who might be an exchange company. This confuses physical occupancy or use with legal or rateable occupation. The timeshare owner remains the occupier. There was no evidence of any formal transfer or of exchange companies acquiring rights under the Club constitution. There is not in our view, any real ‘rival’ occupancy, certainly not one of any weight, in the exchange situation, even the more sophisticated modern system. Nor was there any evidence of anything in the nature of commercial profit or return.
 In relation to exchanges, again, the incidence at the relevant date was a bit higher in the earlier phases. It was particularly low in relation to Phase 7, where of course there was a much higher level of unsold weeks so rather less potential for exchanging. This again fits in with a pattern of owners gradually themselves using their weeks less, but in this case what they were doing was swapping, one way or another, in a way which cannot in our view be seen as business activity or as activity inconsistent with ordinary dwellinghouse use. Exchanges might seem similar to letting by individual timeshare owners, particularly if a week exchanged were to end up being let out, but it seems to us that there is an essential difference. We must focus on the individual timeshare owner’s occupation and use of the subjects. In one case, he is using the subjects to generate income. In the other, he is using them as an alternative form of currency with which to obtain a holiday.
 In reaching this view of exchanges, we do note that in the Forest Hills case no caveat was expressed in relation to the number of weeks used for exchanges, as opposed to the number of unsold weeks used for letting, although the exchange possibility was then known about. Although not specifically considering this aspect of the use of timeshare units, the court would in both cases which came before it have been aware of this feature of timeshare.
 Our consideration of the various uses leads us quite quickly to the view that the appeals must fail in relation to Phases 1 to 6. In contrast to the “Minimum 3rd Party Occupation” figures relied on by the appellants, the main picture, as we see it, at Phases 1 to 6 at the relevant date, is of “self-use” with a significant degree of exchanges, particularly in the older phases, and with a low incidence of letting, well below the level at which the owner or tenant of a holiday home would be regarded as using it as anything other than a dwellinghouse. In short, the position at these units seems to us to be much the same as, and certainly not materially different from, that pertaining in the Forest Hills and Dalfaber cases. As we indicated, we do think, on the basis of the opinions in Guthrie, that the physical circumstances are also relevant. Actual physical use of timeshare units is to all intents and purposes identical to that of commercial self-catering units, but of course that was the position in the previous cases. It may also be quite similar to the position at ‘ordinary’ holiday homes, whose owners may keep them relatively simply furnished and maintained and may arrive one weekend and leave the next, perhaps allowing others to go at other times, possibly occasionally swapping and/or renting out the property. When attention is properly focused on the nature of the occupation and use, we cannot get away from the impression of dwellinghouse, albeit holiday dwellinghouse, use.
 Phase 7 is at least slightly different, because the position specifically alluded to by Lord Coulsfield in the Forest Hills case, did, on the evidence in this case, pertain to quite a substantial degree at the relevant date. The incidence of unsold weeks, with the units used for the holiday letting business, as at 1 January 2005, averaged around 21 weeks (44% of the weeks available). At the relevant date, it appears that half of these units were still more than half unsold, with four of the other five around three-quarters sold. Around 56% of the weeks available were “self-use” or exchanges or ‘Owners Lets’. The incidence of both ‘Owners Lets’ and exchanges was low. Remembering that timeshare owners do not normally purchase with a view to generating rental income and none of the individual owners would have purchased more than five years’ previously – many somewhat less – we can conclude that there is no, or a negligible amount, of ‘commercial’ use to be added to that during the unsold weeks.
 The picture then, at Phase 7, is of an owner using a holiday home for commercial holiday letting for just under half the year, somewhat above the 140 days cut-off for exclusion of ‘ordinary’ self-catering accommodation which is not any person’s sole or main residence from the Council Tax regime, but himself using it, almost always personally but just occasionally by exchanging it, for slightly more than half the year. The physical characteristics of the house, and the form of the physical occupation, seem closer to that of ‘commercial’ self-catering accommodation, where each holidaymaker brings such belongings and provisions as are considered necessary for a week or two’s holiday and does not have to concern himself with physical maintenance of the house, than to private holiday house use, but that does not seem to us to be a particularly significant factor.
 Without embarking on consideration of more or less valuable parts of the year (which would not in any event appear possible on the statistics provided to us), it might be thought that as the proportion of ‘commercial’ letting on average exceeds the proportion required to take non-timeshare dwellinghouses out of Council Tax and into valuation under the Assessors’ self-catering scheme, timeshare units should follow the same approach. 140 days, or 20 weeks, is generally more than half the realistic holiday season. Aviemore, however, is a year-round holiday location, so on that approach the average ‘commercial’ use of the units in Phase 7 is less than half the available weeks.
 We have, in the end, reached the view that in their particular situation as part of a timeshare resort where “self-use” and exchanges play such a large part, the units in Phase 7 should also be characterised and valued as dwellinghouses. Despite the proportion, at the time, of use as a part of a holiday letting business, these units were intended to be used in the same way as the others. Their occupation was regulated in the same way under the Club’s constitution. Although sales may have been slightly slower than anticipated, they were on average more than half way towards the same actual use position. Whatever the position may have been during the period immediately after they were put into the timeshare scheme, when almost all of the units would have been in the letting business, our impression in the particular facts and circumstances at the relevant date is that, like the other units at Coylumbridge and the units in the Forest Hills and Dalfaber cases, they were dwellinghouses.
 As well as looking at Phase 7 separately from the other phases, we have considered whether to distinguish among the individual units. When our view of exchanges is taken into account, there is no individual unit in any of Phases 1 to 6 whose statistics could lead to any different view. Within Phase 7, there is a wide range in the numbers of unsold units at the relevant date. One unit, No 52, appears, for whatever reason, to have been rather slow to sell, with 32 out of 49 possible weeks still unsold (and indeed 21 weeks still unsold even at the end of 2008, eight years after first being offered for sale). Three others had only 12 unsold weeks each at the end of 2004. However, they were all built at the same time, physically identical and all occupied and used under the timeshare club’s constitution, with substantial amounts of “self-use”. It would be tempting, but we think wrong, to consider administrative convenience as a reason for treating them all in the same way. We do note, however, that neither side suggested different individual treatment. The position does seem materially different from that at Dalfaber, where a deliberate decision held three units back from the timeshare basis so that there was no timeshare use at all at those units. We consider that it is appropriate to treat all the units in Phase 7 in the same way, looking at the range of figures, and also the average figures over the group, as part of our overall impression.
 We have therefore decided that all the subjects of appeal should be valued in comparison with dwellinghouses and that all the appeals must, on the main issue, be refused.
 By way of final comment on the main issue, we wonder whether the situation regarding Phase 7 units might be thought similar to that envisaged by Lord Milligan, obiter, in the Forest Hills case. After noting the very substantial difference between the competing valuations (they are, if anything, even greater in this case, whatever view is taken on the minor valuation issues), he said at 303A-B:-
“What concerns me is that I envisage that there could be variations in the arrangements for the provision of holiday accommodation producing cases where it is a truly marginal matter whether the units concerned qualify as dwellinghouses.”
 At Phase 7 at Coylumbridge, a situation has, in our view, arisen in which the proportion of letting of unsold units was such as to make our decision at least a close one. It is of course clear that the rule that subjects are to be valued in their actual state and according to their existing use sometimes takes valuation for rating away from the real world in which the market may reflect potential other uses, but it is the extent of the differences which might once again be thought to cause concern. Perhaps there is a problem with one or other of the valuation schemes (which are rooted in two different principles of valuation, the time share scheme being straight comparative and the self-catering scheme being based in a revenue principle analysis). Perhaps there is scope for adjustment within one scheme to reflect factors which pointed, although not strongly enough, towards application of the other (although it is not immediately obvious why an intrusion of commercial use should reduce the value of a holiday home). However, as in the Forest Hills case, the arguments before us do not require us to consider these matters further.
 In relation to the timeshare scheme which we have decided is applicable, the only issue is the appellants’ claim for a reduction of 20% in respect of the 16 units in Phase 1.
 The timeshare scheme adopts a simple, it might almost be suggested simplistic, method of applying a uniform area rate. As we understood it, this is qualified to an extent by including some reflection of the quality of accommodation in the location adjustment factor, although that would refer more to the quality of the resort and its location and facilities. The relevant Practice Note also refers to the possibility of applying a different factor to new units which are clearly superior (or inferior) to those of the scheme generally. The scheme therefore does not provide for differentiation among units in existence at the time of revaluation and there was no indication that agreed values elsewhere involved any such differentiation. In other words, the settled scheme proceeds on the basis of differentiating within resorts only on the basis of area. We have nevertheless considered whether the circumstances justify any adjustment in this case. We could, for example, imagine circumstances in which a 1980 unit and a 2004 unit with the same areas should not carry the same values notwithstanding the scheme.
 However, on the evidence, we do not consider this claim to be justified. Whilst there are some differences in the construction and design (such as foundations and gable wall materials) between Phase 1, completed in 1981, and Phase 2, built in 1983, and later units, these do not appear to us to be such as to materially influence the rent that the hypothetical tenant would pay. From our inspection of units in Phase 2 and Phase 7, we were struck by the relative similarity in quality between the former and Phase 1 and the relative difference in quality between the latter and Phase 1. We did not see a significant distinction in the quality of the interior design between Phases 1 and 2. Nor did the slight difference in the parking provision appear to us significant. What did strike us about Phase 1 was the considerably smaller size of the units. This leads to values under the Assessor’s scheme of £2750 compared to £4,400 for Phase 2 units with the same amount of sleeping accommodation. The holiday letting rates about which we heard evidence might not be strictly in point in relation to annual rental values, but in our opinion they offer no support for the appellants’ claim to reduce £2750 further, to £2,200, i.e. half the Phase 2 values. It seems to us that the reduction in asking rents for Phase 1 units was to a large extent explained by the size difference. It should also not be forgotten that some differences between Phase 1 and later units would relate to non-rateable items.
 Superficially, the appellants’ claim derived support from the Assessor’s different classification of the Phase 1 units under the self-catering scheme. However, the Assessor’s Phase 1 values under that scheme were £1,575 compared to his Phase 2 values of £1,700, a considerably smaller differential than arises on his application of the timeshare scheme.
 We have also considered whether any smaller deduction than the 20% claimed could be justified. We could certainly see some sense in slightly lower values at Phase 1 compared to the more recent phases, particularly Phases 6 and 7 constructed in 1996 and 2000. However, the Assessor’s Phase 1 values are already considerably lower. We think that tinkering with values in this way, when there is a widely accepted scheme which does produce different values for units of different sizes is not justified.
 We should also express our views in relation to application of the self-catering scheme. The first issue is as to the classification, within that scheme, of the Phase 1 units. For whatever reason, this scheme follows a different method. Subjects are categorized within that scheme as one of three classes - house, chalet or flat - and then graded within the relevant class. As between ‘C1’ and ‘C2’, neither side referred to any comparison: although the chalets at Dalfaber can be seen as comparable, they are not valued under this scheme. In our opinion, having regard to the age and condition of the chalets in Phase 1, they fit the descriptions, ‘Good Chalet – Older chalet dating from the 1970’s – felt or felt tiled roof (or similar)’ better than they fit the descriptions, ‘Excellent/Very Good Chalet – Modern chalet with pitched concrete tiled roof (or similar)’. This produces bed space values of £275 compared to the £370 for the rest of the units. This differential is still rather lower than that found in the Assessor’s application of the timeshare scheme. We would accordingly have upheld the appellants’ position on this matter.
 In relation to the Assessor’s proposed addition of 15%, or perhaps 10%, applicable to all the units, because of the proximity to facilities at Coylumbridge, firstly, we did not understand the Assessor to be relying on Paragraph 7.0 of the self-catering Practice Note, which appears to refer to additions in respect of some common facilities which were not separately rated and could be seen as adding value to the individual units. The Assessor considered that valuing timeshare units in the top location category, ‘Superior Holiday Centre’, would undervalue them. He, however, was unable to point to any other resort at which such an addition was made, although he acknowledged that there would be self-catering units at, for example, Gleneagles and Crieff. Even if we accept that in the appeal settlement of the three units at Dalfaber which went onto the self-catering scheme, the Assessor (not Mr Gillespie himself) forgot to apply this addition, its absence there does not help the argument. This addition was not based on any comparative evidence. In our opinion, the ‘Superior Holiday Centre’ classification, with values significantly higher than at a ‘Main Holiday Centre’ would be expected to reflect both the amenity and the facilities at the location.
 The Tribunal in the Dalfaber case had more evidence relating to this issue, and did make an addition of 10% “to take account of the attractiveness and amenity of the Dalfaber development” (Opinion, page 14). It is not, however, clear that the location category, ‘Superior Holiday Centre’, was in that scheme, and in any event we must proceed on the evidence in this case. We did not consider that the Assessor made out a case for an addition to the top locational rate in this case.
 Accordingly, we would have accepted the appellants’ proposed values under the self-catering scheme.
 For these various reasons, we have dismissed these appeals. If, however, we had upheld the appellants’ position on the main issue, we would have fixed their proposed values under the self-catering scheme.