To be honest, anything that old is going to cost you an arm and a leg, with all the organs in between to keep on the road. The furthest back I'd consider going would be the 1990s, just due to parts availability.
Those are typically Class C's without over cab bed.Fiberglass shell.Terrible MPG but more roomy than a van.Don't rely on owners word.Ask them to have fridge running the night before you see it.If not then consider it must be replaced in your offer.Rust ? In SoCal usually not an issue unless near ocean.Crawl under and look.
Yea, that's it. I will see it tomorrow. He claims everything works, we'll see. Dash A/C needs to be recharged with R-134, no generator(no big deal), both kitchen and shower faucets need to be changed out as they are stiff.