The inside is rough. The original owner was a professional photographer and she traveled with it until the 1980's. She sold it, and the next owner mostly let it sit. The good news is that most of the interior is intact; the bad news is that it looks terrible.
I need to drop the belly pan, get a new axle, and basically start all over. The outer skin looks pretty good- the only dents I see are on the banana skin/wrap.
I don't know how common it was, but she has factory bunk bed attachments.