I had 3 people ring up and want to transfer a deposit over my BMW 540i, took the first one. He then came down, gave me a bank cheque for the rest and drove off. (Didnt even look at the car)
i had a corporate check for my 33 GTR though. I just simply said car does not move till cheque clears, which it did (Also paid the extra fee for it to be cleared in 2 days). Another one who saw the car, loved it and paid. Didn't bother negociating.