Another tip, never ever let them know you have outside financing until you've agreed on a price and have it in writing and signing. As mentioned this is where they make their money and will "sell" the car at cost (some times less) to make the sale then make the money back on the financing.
A friends mother bought a new Fusion last summer, they made the deal then in comes the finance dude, his mother starts writing out a check for the total. When finance dude sees this he tries his best to convince them to finance, and "save" your money. After a few minutes of the back and forth crap, they got up to leave commenting that it looks like they weren't buying a new car that day.
Also procrastinate...A LOT. They see your sitting on the fence they'll start chipping away a little to bring you on there side of the fence, stay on that fence they'll keep chipping away. Works not only with new and used cars but appliances as well.
Some times (with appliances) there are a lot of extras built into the sticker price like extended warranty or extra attachments, for example I used to sell Electrolux vacuum cleaners, in the price, say $500 we had extra attachments, a years supply of bags and extended warranty. If people just didn't commit we'd drop the price to $450, unbeknown to them we simply removed one of those extras, say the $50 attachments and dropped the price accordingly, or some times we'd "throw in" the attachments for "free".
Some of the dealer add on junk, like under coating or "paint sealer" (wax), or pin stripes, you can get them, if you work it right, to take off. Once you pick out your car and have a price, look over the itemized list and insist you don't want that done, even though they already did it, act like you thought it was done after you checked off the box for them, and keep insisting you didn't want that stuff and wouldn't have asked for it. If they see your pretty adamant about it they will take the cost off. One dealer wanted $75 for rubber floor mats, I told him to take them out I could get the same ones at Wal-mart for $12.99. He scratched it off and noted 'customer doesn't want floor mats'. When I picked up the car they were still there. I started to had them to him through the window before driving off and he just waved his hand to forget about it. Gee you'd think something of that value they'd have been more concerned about it!
