Busses are collectibles because of their business model--create something for production, then never offer it again. Like most collectibles, the farther they are away from their original conditions, the lower their prices will go. But the price is also subject to a bunch of stuff, though, like age, value to the buyer, rarity, so on. But I can't think of a time when someone would sell or buy a mint Busse for less than a stripped and polished one, unless maybe it was stripped and polished by someone like Ban, who did some pretty epic mods and has since stopped doing Busse mods.