'72 SS $2700 Ellensburg, WA
Skin tears are the biggest concern, IMO. If they admit water then interior damage will result. If on the underside, then an entryway for mice & rats. Check behind awning attachment points and lower; around doors and windows (shrunken gaskets), along interior panels and flooring. Replacing the floor is a pain.
Big bad dents are a no-go for me, also. One can live with them in some cases.
Plumbing breaks are second: toilet, undersink, elsewhere. Check for rot everywhere if you suspect (or smell) moldy/musty.
No breaks or bad cracks in shower pan.
The trailer is missing the front window and front side window covers. Ask about them. Not the sort of thing to be found except on another trailer.
This is almost a giveaway price (in ad referenced). Assume that every appliance needs replacement or being re-built, along with floor covers, curtains, mattress/boxspring, and fabrics. Every system will need attention and work (updates).
One can bring it to useable status short of doing all the work, but ones appetite for this work should be substantial.
Assume all new tires, that brakes will need attention; wheel bearing service
before being moved.
Search on this site for buyers trailer checklist, it'll work fine to take you through what you want.
If on inspection there appear to be no substantial tears that admitted water, and that the front window covers can be located, for that price you have a nice project.
For about double that $2700 or more you may be able to source a better trailer. There are several in the NW at present that look like good candidates. Were I to buy a trailer of this age at that price I would want a $4k budget just to bring it to being roadworthy and system-safe. This is before any work on appliances or cosmetics. It's enough money to get it home and a few basics out of the way.
I would travel to inspect this one as reference as an RV dealer has it for sale, it likely is in very good working condition:
Portland SS. The changes over time were minimal.
After seeing a nice one you'll have a better gauge of what a lower-priced one is worth. Appliances are generic, non-brand specific.
.