I bought a class C that was in "pretty good shape" and was 2 years out of having received a state inspection. I paid too much for it and then had to sink more money in to it to make it pass inspection on the CHASSIS side alone. I spent 4 or 5 years patching leaks as they popped up and tinkering with little fixes here and there but by no means did a restoration. I was done and sold it for a loss because I made sure every issue I knew about what known to the purchaser.
Campers and camping generate enough issues to satisfy my tinkerers gene. I don't want to invest and engage in a restoration at this point.