You going to frame it in? I've seen people do that, quick easy way to build a garage for sure. I'd think a foundation wouldn't be as big of an issue either with the light weight? I've got a boat too, 1970 Sea Ray..... sometimes I wish it would catch on fire and disappear.
It has 12" pillars 6 ft down for anchoring,
after removing a bunch of the gravel,
I'd poor 6" of reinforced concrete...
Aluminum/sheet metal .25ga. stud frame the sides & back,
it's self supporting, add some shiplap panels or maybe even more tin/steel
I'll add a side double 2 x 3'0" steel security door &
2 commercial roll up doors a 12'w x 12'h & 12'w x 14'h,
a 4 post lift & a 2 post pref., on the high side, it's over 14',
with a pit on the lower side, sump just in case & a steel cover,
that lower side would be my tool area & main work benches,
fabrication area, compressor, welders, pisser & maybe a sink in the corner...
I love concrete, the whole back area will eventually be concrete...
I will spray insolate the enameled steel with foam inside
& put a propane heat & air handler, that use to be in my house
some killer lighting, ceiling fans etc.
I had it all planned out, never thought ol' dad
would be still wanting to Rv-ing/travel this long still...
I don't want the stuff left out in the snow & sun etc.,
it ruins chit...LOL
Yeah the boat is from 1977 Glasspar, bow rider tri-hull 50hp Merc...
Yahoo !!, It could go away
or burn, but ol' dad still likes to fish,
I may have to live with it, for the duration, out of respect...LOL