If a dealer sells at invoice he still has a profit margin. How much that will be depends on how long the Viper was on his floor plan. Dealers do not outright "buy" their inventory. A dealer is charged for a car by Dodge when it gets invoiced which is usually right around the time a car is shipped to the dealer. Think of the dealer as having a credit card with a huge credit line. The dealer pays interest on the amount of money he is charged for the vehicle (and all new cars he has). Each month a car sits unsold he pays the interest on it. Again just like a balance you keep on a credit card. Now to encourage dealers to take cars and hold them in inventory the manufactures give dealers a "holdback" allowance. It varies from manufacturer to manufacturer and ranges from 2-3% of the MSRP of the vehicle. Dodge's holdback is 3%. In a simple example with an 08 Viper, if it had a list price (MSRP) of $90,000 and an invoice price of $83,000, the dealer would pay $80,300 (invoice minus the 3% holdback allowance). Added to this($80,300) would be any interest he owes on the vehicle. So if the car sat in the showroom one month before he could sell it he would also pay one months interest on the $83,000 invoice amount he was charged. The dealer would pay $80,300 plus the one month interest. If the Viper was ordered by a customer it would not sit in inventory and cost the dealer interest waiting for it to be sold. So even if sold at invoice the dealer would make $2700. As you can see a Viper (or any other car) that is ordered by a customer represents the best deal for a dealer since the car does not sit on his floor plan to cost him interest and the he keeps all of the holdback. You can really see how bad a dealer wants to move a car/truck when he "goes into his holdback". A good example of that now is the steep competition in pickup trucks. Many DOdge dealers are selling pickups below invoice and splitting the holdback with the customer. Of course there are other incentives going on but that is another story.