It looks like a nice truck and the dealer that has it knows the 7.3L are worth there money, so I'm not sure how much you can beat him down on the price. But it is a low mileage truck and depending how much weight you are towing should not be a problem ounce you swap out the stock transmission cooler for a 6.0L one. I'm not sure how far it is from you, but don't get sucked in by the pictures, you want too see it first hand, I had too purchase a used truck too replace mine that got wrecked
and ya I found some things when looking at it, like the valley on top of the motor was wet looking, but the owner said he just had the fuel drain valve fixed, so I just figured it wasn't cleaned well. Wrong!!! I think it's the HPOP seal's so know it's off to the shop, when I started digging into the truck, the fuel filter and bowl where horrible, the transmission fluid was questionable, the rear gear lube had probably never been changed, so I'm a little pissed at myself but for the price and what money the insurance gave me I had too jump on the deal.
But my wife has watched me nurse the truck, and she said "it's in good hands now"
Good luck Bro, and keep us informed on what you deside