Forget about that idea. You'll hardly win because:
i)they know that particular car's market price (based on its
conditions) but you don't. if you bargain too much, they won't
sell. If you bargain too little, they know you don't know much
about cars - a carrot head.
ii) even if you manage to get a good bargain (when hell freezes
over), the dealer will find ways to recoup the "loss". You'll find
additional payments like GST, agreement fee, and what-have-yous.
Most of these payments only crop up after you have paid your
deposit so you LL but have to pay the dealer.