In reply to Philip:
> (In reply to Mattyk)
>
> Are you a first time buyer (or not non a chain).
>
> Offer the asking, then screw them down on price just before completing.
Has anyone ever told you that you are lowlife?
In any case what you suggest - as well as being just plain nasty, might backfire badly. Remember that the seller pays out very little until the house has sold, but by just before completion the buyer has already paid a lot of money in search fees, surveys, etc, which if the seller says "F*ck you" (and if it was me, I would (1)), you've lost.
Also, word of buyers like yourself gets around, and estate agents will share notes.
(1) When selling I rejected the highest bid for my property as those potential buyers started playing silly games (2), and actually sold for a much lower price to a young couple who fell in love with the house, played no games at all, and scraped every penny they and their parents had together to buy it.
(2) And then refused to deal with said buyers even after they appeared to stop playing games, because they had by then annoyed me.