Buying a 2011 Hyundai Veracruz, and saving $6000 off of MSRP.
I made my calculations based on the Whole Sale Price Report and simply presented them along with a copy of the Report to the salesman. The manager made a slightly higher counter-offer which we happily accepted and the deal was done pleasantly, painlessly and within ten minutes.
Buying a 2011 Hyundai Sonata, and saving $1500 off of MSRP.
The dealer cost is very helpful in knowing from where to start negotiations. Remember though, that the better initial price you achieve the lower your value of any trade in will become. A lesson in reality.