Tom, many of us have found abandoned boats to be worth substantially less than the cost of the match to set them ablaze. No doubt there are some perfectly good ones that have been abandoned for insurnace fraud and other reasons, but the vast majority? Are holes in the water and no one wants to get stuck with the disposal bill, or the wreck on their property.
If you think there really are good prospects out there, I suggest you start a 501(c)3 organization to locate, move, and match abandoned boats with people in need of them. Everyone will thank you, for removing the hulks and creating the housing, and you should be able to make a buck on it at the same time.
That's assuming the boats you think exist, really do exist in any quantity. One out of a hundred doesn't quite count, you still need to deal with the other 99. (And personally, I'd expect it is more like 1:1000).