one way to get a good deal is compare prices. if this guy gives you a deal, you say that the other dealership was better. for certified cars, since they are limited, there are a lot of ways to get them cheaper. all you have to do is be straight, aggressive and a little down.
be straight and aggressive. tell them you love the car, but hate the price. a nice thing to do is NOT give numbers to them. let them try their best and you say no, sometimes they go down more than the price that you were thinkin to pay. if that doesnt work out the way you want, just give them numbers you want to pay and start agreeing on it by going a little up or down. another thing to do for certified is complain. bring an ad and show another dealer is giving the same car cheaper. say the mileage is too much nomather there is warranty or not, and the price doesnt match the mileage. say you expected a body kit with it, or the rims arent anything good looking, or you wanted the interior leather or cloth seats. the color is bad. they can give you little discounts on this kinda stuffs. everything is worth the try to rip them off. good luck. go with a mechanic to check the engine, suspension, etc... if the suspension is worn out or anything else, thats another discount. and ask them to change the lift bolts for no charge and belt tensioner.