There's rust and then there is rust! Rust in the floor, sills, doglegs chassis rails and hatch shut panel is one thing, common enough and there are plenty of examples of how to fix with either enough time or $$s. But rust around the perimeter of the roof and in the windscreen frame down into the A-panel in my opinion takes the job to a whole new level as evidenced by my poor old rustbucket.
I agree with Simon that it's a 240z and it's worth whatever it's worth to the adventurer who buys it, but I disagree with the "faith and trust" I've been shafted every time. I really hope someone does get to buy it to restore, but does so accurately informed and well aware of what they are likely to be getting in to. I'd love to add it to the collection but personally would not gamble much more than $1k.