I'll take a picture of our 2007 with an OEM hitch. It was easier to install than the X5 version, and there is no recoding required for the vehicle. There are some good posts with pictures if you decide to do it yourself.

There are four different bumper versions according to the hitch install instructions, all with slightly different trim pieces. For ours, I trimmed it back very close to the square receiver, covering the plug. You can access the plug from below, or clip the cover out if you like. I usually clip the cover out when towing since it is easier to get to the pin.

Internal bike rack - never considered it. If bikes are dirty, wouldn't want to put them inside. It does take up all the luggage area. A hitch rack is reasonable for mountain bikes, particularly if it is a good one like the Thule T2 that holds the frames or wheels, and doesn't just let them hang. I prefer a roof rack (road bikes). Lots of threads, particularly in the X5 section of this site. Seach on bike rack.

BMW nav on the X3 is a waste of time IMO, even more so than on the X5.

For the iPod, you can use the Dice (see the links on this site, board sponsor) or the BMW kit. I just use the aux input behind the centre armrest. I had an earlier version of the Dice on my X5, worked fine.

Welcome to the board!

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue