Dusting off an older thread here... and I'm sure you've probably already gotten this fixed, but my wife did almost the same exact thing in our X3 last fall. And I actually decided to let her drive the car through, just in case... well, just got it fixed and it came to about $2300. Hers was the M-Sport package with PDC sensors in the rear bumper (at about $200-300ea, I heard), although I think she was going a little quicker than 3mph. Anyway, they're certainly pricey to fix, thats for sure...