My plan was to stay pragmatic. Even though the worst damage was at the bottom, I understood the problems were on the top, the middle, and the beltline. Fixing and replacing all the top stuff is a job that needed to be done and it doesn't cost a lot. I had all summer's rain storms and soakers to work on leaks and test my work.
On top, I replaced the antique air conditioner, replaced the 3 crank up roof vents with leaking covers with FanTastic fans, re-sealed the two sewer vents, and re-sealed the top awning channel and body seams. That cost less than a grand. Then I replaced all the window gaskets and the door gasket and added solar film to the window glass. That took some time and it didn't cost a lot. That all needed to be done just to maintain what floor and frame was left.
After I had all the leaks fixed and tested, I fixed the frame cross member, added bubble foil insulation to the floor and walls where I had wall panels removed, replaced sections of the floor, and moved to replacing fixtures and appliances.
I've increased my vocabulary and added to my skill level in several categories. No matter how this trailer turns out, it's a project I'll never forget.