Island Packet ?
I personally would not consider them to be more valuable than a comparably sized boat (especially when by size I mean more than simple length on deck), but I would guess that the price for these boats somewhat reflects their argueably undeserved cult status. I suppose that you could argue that their price may reflect a number of possible factors as well, such as:
-They offer a lot of room for their advertized length on deck,
-The offer a lot of displacement for their length on deck,
-New they were on the more expensive side of things than most boats of the same length, build quality, or displacement.
-They have picked up some of the perception of being well constructed that, argueably, derives from the later model Island Packets and more to the point, the marketing that went with the later model Island Packets.
-Asking price is not sales price and so the asking prices may be inflated by one owner seeing another owner''s asking price. (Quite a few years ago a broker who at the time specialized in selling Island Packets said that asking prices generally exceeded their actual sales prices by a larger amount than he saw with most other boats that he sold),and lastly
-There is no accounting for taste (he said with tongue firmly in cheek fully expecting to be blasted by someone who finds these boats right in line with their taste in boats).