It can be done. Make sure you get a "Bill of Sale" from the seller, even if you have to write one up yourself and have him sign it. He should make sure he gives you a heck of a deal, since you have to go thru the hassle because he did not do it correctly when he bought the boat. Check and make sure the boat has a legible serial number stamped on the serial number label and that it is not scratched off. (A scratched off serial number would be nearly impossible to register since it would be assumed stolen.)