U.S. Base Invoice Price for 2012 X5 XDrive 35i sport?

[COrth]

I am shopping for a new 2012 X5 XDrive 35i Sport and in the process of negotiating with a few dealers for the best price. In an effort to negotiate wisely, I am working from invoice price plus a certain amount. However, one dealer is reporting a different base invoice price for this vehicle from what another dealer has reported. There does not appear to be a discrepancy in the invoice price for the options that I am choosing. Edmunds.com and one of my dealers is reporting the base invoice price for the 12XH as $52,715. While another dealer is reporting $53,085.

Can anyone confirm what the base U.S. invoice price is for a 2012 X5 XDrive 35i Sport (internal designation 12XH)?

Thank you.