he asked about real boats. Not blowboats, or blowup boats .
My main concern would be with ethe wiring. Even good copper wire would be destroyed in 2 days under salt water. Rewiring a 60' boat with properly tinned wire would cost$$$, not to mention, you'd probably have to lots of work to even get to the wiring. new motors, unless those 502's were pickled, new fuel tanks$$$, generator, electronics...
sounds like a great project, but my guess is you would spend over 100K to do it right, and you'll still have a salvage title following you around.
however, living on the water is like nothing else in the world, and i love my two boats docked out in the back yard, and would give up almost anything to stay.
'89 Dodge Raider V6 Auto
'90 Mitsu Montero V6 Man
'01 Dragon VX
'05 Scion xB