Not running may be in your favor. If you have a trailer and can get it on the trailer and get it home, you'd be much better off not trying to get it running right then and there. Just yank it and get it home for as cheap as you can. The price may go up or the deal may fall through if the car is running.
I went to look at a foreign compact car for a female friend of mine. We were told it didn't run and the brakes were frozen and couldn't be moved. A few minutes with a battery and some tools and the car was running. A quick blow on the drums and the brakes were freed up. Then the mom comes out and kills the deal for a $125.00 piece of crap. I was a little pissed and should've charged them for my time and knowledge, but I just took my battery and told them to keep the P.O.S. They called my female friend a couple days later and said she could still buy the car if she wanted!!! She just told them to keep the P.O.S or call the junkyard!!!
Get it home before you do anything with it, Geof