so you didn't buy it in the first place but:
the seller was being a cunt for asking you to come down to have a look even after he'd taken a deposit on it
you were not very sporting in going to have a look at it even though you knew someone else was after it
what would you have said to dave if you'd come with some spare change in your poket to collect his car and he'd sold it 5 minutes before hand?
not best pleased i would wager
but to your poll, i would have fooked him off for asking more money