I bought a 1985 TT in 2010. Here is what I learned:
DO NOT take the seller's word for anything. If they won't let you hook up the water, leave. If they won't let you light the water heater pilot light, leave. If they won't let you plug into electrical, leave. Test all the appliances. Have them turn on the fridge the day before you visit so you can see it gets cold.
Water damage can be a big deal, but it can also be an easy fix. There was some staining and soft spots in my TT - they were only found at the corners of a couple windows and one ceiling vent. Yes, those windows and the vent leaked, but it was extremely easy to clean them up and re-caulk them and there were no more leaks. The damage done by prior leaking was minimal and did not affect the integrity of the TT.
Be smart. Check everything. Trust nothing.
1975 American Clipper RV with Dodge 360 (photo in profile)
1998 American Clipper Fold n Roll Folding Trailer
Both born in Morgan Hill, CA to Irv Perch (Daddy of the Aristocrat trailers)