That is precisely what I did when I bought the Sentra back in 1985 (and why it took 3 weeks to do it). On that deal, I walked out and the dealership kept calling me until finally I got the car for what I wanted ($500 above their cost).

I guess the old way is still the best way. ;0)

[Edit]: Back in 1985, Tercel's in NC were going for $1,000 to $2,000 above list. You got on a wait list, they called you, you came in and looked at the car, voted up or down and then paid through the nose. I wasn't going to do that and the Sentra was my next choice. If I'd have purchased a Tercel that year, in that region, I'd have paid over $10,000 for what, essentially, was a Sentra with a Toyota logo.