Maybe $500 for the tires and wheels, but only IF you like them. Otherwise used they are not worth anywhere near that. Maybe brand new, what with tire prices being what they are, but I don't see anything exotic there at all.
He probably does not really want to sell them because he might be able to use them on another rig. He could have paid that much new, but that does not mean he can get it back. Unfortunately for anyone once they become the "seller" rather than the "buyer" of said stock.
And he'd better have a receipt for the tires, or you should know how to decode the date stamps on the sidewall. Anything over a year old and their value goes way down. And unless you can start to utilize them right away too, new tires are not worth anything to you if this is going to potentially be a multi-year project.
Would not be the first time a brand new set of tires went to waste sitting in a driveway or pile in the corner of the garage.
Neither truck is a gem-in-the-rough. They're just rough, as most are at that price. Certainly not out of line on the pricing for either one, but there ain't a corner that won't need to be touched on either of them. So just be ready for that no matter which one you choose.
Paul