How much is the guy asking? I know he may not go for it but I always tell people I will pay them after I install it(on expensive parts) so if it is bad I didn't just waste a whole bunch of money. I even let them watch if they are worried about me not paying them. But Just make sure the trans isn't locked up or anything. Pull off the drain plug and see if there is metal shavings on the drain plug. Make sure the input shaft isnt all sloppy.