A lot depends on who you would sell the full car to. Some stranger on craiglslist is not really going to pay anything for a car that 'needs work'. Someone on here though might be prepared to pay more for it if it is savable.
So the main question is, what's the chassis like rust wise. Everything else is fixable/replaceable but a rotten chassis is a death knell pretty much.
Anything I might say is probably worth what you paid for it, so treat it accordingly!