In the market for an F

Hello forum members I'm a first time buyer and would like some suggestions. Currently I've visited a few dealers, very few of them have the car that I wanted. The car I want is a '08 Smokey Granite Mica IS F fully loaded. Currently there's this other dealer selling a Mercury Metallic for $56,900 at first then they dropped down to $53k. The deal sounds real good and I don't mind settling for the Metallic over the Granite. But a friend who also works in the automobile sales industry is telling me to hold out some more about close to $50k. I have a few question and hopefully you all can lend me a hand. Do you guys think that this is a smart move to hold out? What type/brand of tires did your F come with? Is it possible to request for a specific type of tire and replacement for a brand new battery after reading a post from one of the owner it got me thinking. Also the car might be sitting on the lot for a while so I'm afraid the current battery might be kinda weak. For those who have an '09 what was the price for the F that you got? I currently have about 2-3 more dealers to go to and 2 of the dealers have the smokey granite but I'm not too sure if they're fully loaded or not. Hope to hear from you all soon.