Find out if the guy has all the parts, except the tank. The bike actually looks clean. 4Ok clicks is not a lot of miles. Mine had 96,000 and hadn't been running for 9 years (ok, maybe it was started a couple of times in 9 years....hard to know). But it hadn't been licenced for road use in 9 years. The gas was putrid, the interior of the tank was coated in some beige crap (which took a lot of work to get out), rubber bits were mostly done (brake lines are original) and the crankcase oil was bunker B. Oddly, the brake fluid was clear. I had service records to 42,000 miles and then it stopped.
Took her apart, cleaned and greased, re-assembled and it's a match made in heaven. She runs better by the mile. Haven't touched the injectors. Did have to replace a fuel pump but only because I broke the brittle plastic connector off trying to remove the fuel line.
If the guy can give you a comprehensive accounting of the bike's past it may well be worth making him an offer. I paid $1,400 CDN for my bike and put as much into it...plus innumerable hours of labour and love. You'll only get her out of my "cold dead hands!" at this point. Do your homework on the tank first. Gryph was good enough to source fuel pumps for $20 US. You're on the border. That should be easy.
Don't pass her by just yet, in my opinion. Go to the guy with your well-articulated argument and concerns and make him an offer.
We should be restoring Bricks, not parting them out....imho!
Good luck
