I hate to say this but it could be either one. Depends on the owner.
Maybe just talk to the guy, tell him you are a Pinto person and would like to see what he has. If he seems receptive then see what happens from there. Maybe he is waiting on someone to help him restore it, wishes he never saw it, or he is waiting for it to finance his retirement. You just never know.
If you end up offering to buy it, have cash with you. Most "buyers" in these deals don't have the cash and that ends up getting the owner po'd at everyone.
It also depends on your area. It could be a $500 car, or $1000 or higher. In AZ a rust free car is normal, in Ohio it is extremely rare and brings a lot more money.
Russ