We picked this trailer because the exterior was in great shape. It had all the windows and no major damage to the exterior skins. The tail of Tiangong sags; So does the shell around the edges in places. The first step in our renovation is to get the frame beefed up. In order to do that we first have to remove the subfloor so we can see how bad the frame is damaged.
To speed up the survey of the frame I cut holes in between the steel frame. This allowed me to get a look at the frame and still have a little wood to walk on. The old self tapping screws were very securely rusted in place. I tried muscle to remove them and quickly moved on to pretending I was an oil company drilling for black gold and drilled through the subfloor right next to the screw and flooded the mine shaft with WD-40 then let it soak overnight. Perhaps WD-50 would have worked on all of them; I ended up grinding many of them on both sides of the frame and punching out the little pancake of the bolt still rusted in the frame. What seemed like mostly rotten wood was a real pain in the ass to get out.