It's gotta be a typo. No one would try to sell a 23 year old boat for twice what a new one would cost. Someone makes a dumb mistake and the knives come out pretty fast. I really can't believe folks are so intent on sitting at their keyboard and trashing some stranger on the internet there's no thought to give a guy the benefit of the doubt for an obvious mistake. If you're looking for the boat, shoot the guy a note and tell him it looks like a typo on the price. If he's serious, then make a big deal about how crazy the seller is.
Nothing in the world is more yielding and gentle than water. Yet it has no equal for conquering the resistant and tough. The flexible can overcome the unbending; the soft can overcome the hard. - Lao Tse