Boy I'm not sure where to go on this one.
I would think you would be able to find a better MH and in better shape. The Class C looks promising.
I bought mine going on 5 years ago for $4500 44,000 miles and 250 hours on the gennie and have put around 10,000 miles on her, have had the exhaust fixed(my choice) and 2 fuel filters (Broke down)
No leaks. I would look for/at Fiberglass siding MH's I'm not sure if they have the problem with delimitation though mine hasn't. I know your in a crunch with child on the way.
Have you asked your mom if you can stay there while redoing it she might not object ?
Again not sure what I would do, but keep us informed, will be a interesting read.