Whether the boat is salvageable depends a lot upon what it is made of. If it is all fiberglass, maybe it is worth the work to save it. If it is fiberglass over wood, the best way to make sure it is worth buying is to require the owner to have the boat hauled out, using slings, for a survey. If the slings go right up through the hull when they lift it, you know this is not the boat for you, and the owner, of course, is screwed. We saw this happen to a big cat right down at the marina at the end of our canal when we were living aboard our boat back in the early 1980's. In the case of boats built with fiberglass over wood, too often the wood inside the fiberglass shell gets rotted.

There's a big Rudy Choy cat at a marina right down the street from us, and we have been eying that for a year or so; but, again, you don't really know how good it is structurally until you have it hauled out of the water.