My theory goes...
In the same way that an artists paintings jump in value as soon as they die - people realise that supply is limited and demand grows exponentially (as long as it's a good artist) - transpose this simple analogy to any other object that has gone past the depreciation point - when the availability of them goes past the point when there are surplus items in the market compared to demand
The demand increases as more people become aware of their value (not monetary as such but lifestyle based in the case of VW) - this has been highlighted by the appeal of the classic VW brand in marketing to associate a particular lifestyle or message, perhaps of times gone by when things were simpler, like getting in your camper and heading off into the unknown
So this increase in awareness into mainstream society from the relatively small community when they were in surplus - coupled with the reduced supply of vehicles - means that we now have more buyers than vehicles and the perceived value increases of each one as it would in any market
But as with any commodity (apologies for referring to the market in VW's in this way but it helps explain my theory!) external pressures will affect value - in a recession goods that are deemed as luxuries (i.e. you could live and feed your family without a classic VW) will be affected by a smaller number of potential buyers and the supply vs demand balance is redressed slightly - those who can afford luxuries will be looking for the best possible example, the entry level buyer will either wait and see what is happening with personal circumstances or reduce their capitol but still attempt to buy the best condition vehicle they can
This would manifest in decent buses at previously sensible money taking longer to sell with more competition from similar vehicles, meaning they don't sell or reduce in price to meet the buyers capability - whilst exceptional vehicles will still enjoy the same ratio of buyers to vehicles
Not to add into this the recession meaning that more vehicles may be on the market further driving down value - but like all markets they can go down as well as up - and the fact that there has been sustained investment in vehicles so confidence is high, I'm sure once people have more disposable income they will go back to their previous levels
Certainly now is the time to buy (if you believe we are heading out of recession!) - otherwise I'd sit tight, ride out the storm and sell when we are in better financial times - don't think the bubble has burst (meaning people have realised that perceived value is too high and it's an adjustment in value in the market ala dotcom burst) - think it's more just another sign that we are in a recession and value will drop, and not just our buses but everything that fits into this category
Suppose the trick is to spot the next big thing, would have to be an exceptional piece of engineering that conveys a particular lifestyle that there is currently a surplus in the market off......V8 petrol range rover anyone?
I should clarify..I didn't buy my bus to associate with a brand, I didn't buy my bus as an investment, I didn't buy my bus because I'd never seen/considered them until I saw one on the TV - always wanted one, couldn't afford one til now (bear in mind that everything was expensive when I bought my first ever car (a Triumph spitfire)) - it's taken me this long to work up to a VW and everything else has been going up in value at the same time.....I can however say that my bus is the first vehicle I've ever bought that will go up in value - which is just another of it's many appeals, and why I love it so much