Gbopp - Thanks so much for confirming my suspicion.
I went back to the trailer today, and was able to sand the walls - with some 60 grit to pull the paint off and then rough up the walls.
What shocked my wife was when I took a scraper blade, and just pushed it up the wall, and the paint peeled off like it was held on with a static charge.
She was shocked.
So, after a few hours of sanding, and elbow grease, and more hand sanding and scraping, it's all roughed up, repainted, windows and doors cut in, and ready for wallpaper.
thanks so much for the prompt reply!
josh