Annie, I described it as a project boat only because the engine isn't running, and if I bought her I'd be trying to bring her up the west coast of the US in a series of short coastal hops. From what I've read, that requires a lot of motoring at any time of year. But Duane doesn't know why it's not running, only that he "can't turn it over". I guess that could mean anything from the crank is too stiff for him to there's a rod thrown. He has a new head gasket, so I suppose the first thing to do would be pull the head and see what's up. If I could take about a month off work and just sleep on her where she's anchored, I expect I could get her running and bring her at least part of the way up.
Nicholas, I'd never heard of an ultrasonic thickness gauge before this - they look really handy. From what I've just read about how they work, it would work whether the boat is afloat or not. It also looks like you'd need one that has an echo-echo or multi-echo mode, or else you'd have to scrape or sand through the coating to bare metal. What make/model do you have?
Duane (the seller) said he's had her hauled out several times at Berkeley Marine Center.
http://www.berkeleymarine.com/yard-rates
Jonny, it's Sabb (marine engine manufacturer). Saab is the Swedish car maker, but as far as I know they've never made marine engines.
David