How about just meeting the guy at HIS bank and have them make you out a bank cashier check or even better set up a wire at his bank and once it clears release the boat? Also make out a good bill of sale receipt signed by both parties stating that if for any reason the payment is rejected you will immediately retain possession and all costs associated with obtaining the boat back will be paid by the buyer. Make sure to copy his drivers license, confirm his address is accurate and do a quick internet search on his name is see if anything "funny" pops up. In other words, cover your ass.