I just bought an 08 txw175 as part of the steal of a deal promotion. That promotion already had the boat a couple thousand below prep and freight price. After some haggling i got them to throw in a $250 gift card. I tried for 2 gift cards and they said "see ya". I walked. Then went back and did the deal.
From what i learned their cost on the gift card is half, and the rep makes 3% i think. So if he is making 300 bucks he might be willing to throw in a 100 buck gift card (costs him 50) to get the deal done.
Haggle until they say no.