We owned 2 bunkhouses. A Springdale that was metal sided and a Cougar that was fiberglass. The only problem we had with the Springdale was an outside shower knob that took flight one afternoon. Keystone sent a new shower assy and I installed it.
Both had wall and door bunkrooms. Now the kids are grown and we have recliners and a couch.
The suggestion about dealers is very good advice. We have 3 dealers in our area. Two I wouldn't consider dealing with, the third is great. They give a 90 day warranty on used 5ers. It's a real simple warranty. Anything breaks in the first 90 days they fix it. They even change at the mattresses on all their used rigs.