BMW dealers are set up to sell in their own territories. They buy cars from regional BMW sales companies (BMW NA for the US, BMW Canada for Canada, etc). Whereas a dealer might like an incremental sale, the marketing company has an exclusive. As a result, you need to deal with your local dealer, unless you have a US military channel to purchase through, or something like that.

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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