800's good.. but
and I'll say this again.
you took / are taking a gamble.
it's not 'taking advantage' of somebody to not pay top dollar for a NON running machine.
i've seen plenty of non runners I would not pay over 500$ for.. but I offered to get it running for the op for a small fee.. and if it ran.. then they could deduct that from the purchase price.. if no run.. I'd not charge.
thus a win-win..
heck.. I've fixed the steering on a tractor for an old guy down the road.. and I had no intention of buying it.. but he couldn't manhandle the spindles... a real win-win for him.. :)