My wife and I bought and lived on a houseboat back in the late 90's. It was a house on a barge that we bought for 15K including a 20' Proline as a tender. Sold it for 20K, 4.5 years later and saved 60K for a down payment on my first house. Had a blast living on it. Worked out even better than I expected! LOL.
My nephew on the other hand, wanted to follow in his uncles footsteps when he was in high school and paid 4K for a 53' wooden Mathews powerboat with no engines. Uninsurable, he finally found a boatyard that would let him keep it there for some sweat equity in yard work. I think it lasted 1.5 years before it sank at the dock. Luckily no engines, fuel tanks, ect so no environmental clean up. Despite this, he was lucky it wasn't much more expensive for him.
I also had a friend who bought a 34' X 17' ferro cement sloop rigged catboat and lived on it for a bit. This was over 20 years ago and the yard didn't require insurance(luckily) as it was uninsurable. The boats name was Metamorra, but we just called it "More Mortar"
He had a hard time keeping bottom paint on the bottom, until he coated the bottom with UGL(the foundation water proofer) and then applied bottom paint.
He tried selling it many times with zero interest. He finally bought a house and hauled it and put it in his yard. It was so heavy it sank into the ground quite a bit. Finally ended up breaking it up with a jack hammer.
Take others advice. Free boats are far from free. FC boats are a nightmare.