1) if buying the next year model (in 2011 buying 2012 model year), add 2-3% over invoice price plus all doc fees
2) if buying at the end of model year, substract 2-3% from invoice price
3) If there is a buyer incentive, substract full amount of incentive from invoice and then apply 1) or 2)
4) If there is a dealer incentive, sustract half amount of incentive from invoice and apply 1) or 2)
Dealer also has hold back to make the profit.
For all kinds of information on incentives and invoice price, go to edmund.com to find out.