Buy that shit or I'll be on the next flight to Philly.
Seriously though, as long as it's not a complete rot pile, you could probably flip it for a quick grand no problem if you don't end up wanting it. The problem is that if it gets its claws into you, it could end up costing you. With that kind of mileage it's probably time for heads and trans to be rebuilt. They can go longer though. I'd rather have an R80G/S with miles on it than one that sat for decades. I've seen a G/S w/ 400,000+ miles on it being ridden around the world 2 up with nothing but a head rebuild and a trans rebuild in its history. You mentioned that you like wrenching, well these bikes are a pleasure to work on. Everything is out in the open and easy to get to.