I agree with Big Ed 100%. Start low, and see what happens.. He might say $25 bucks and then you have a great deal.Heck, if the engine you saw is complete with nothing broken/missing, any counter-offer up to $50 bucks is still a fairly good deal, as long as it runs.. But don't forget, the 310 doesn't have smoke or choo choo, like Al said. Not running, I would offer $50 dollars for it, but only after haggling, I wouldn't go anymore..