In your emailing, make sure to ask the dealer to include MACO (advertising fee) in his quote. Some dealers include it and other (sneaky) dealer's do not but then "surprise" you with it later--now you know why they quoted you ~$300-400 cheaper than another dealer who included it in his quote to you.
Make no bones about it, MACO is included on the invoice sheet of all BMWs sold in the United States.
There is an excellent thread on this in the Ask a Dealer forum...spent some time browsing over there and you'll learn a lot.
2001 530i/5 (E39), Topaz Blue/Stone Green/Black (sold) *very rare interior/exterior color combo*
2005 545i/SMG (E60), ED Order, Titanium Grey/Grey (lease over)
2014 335i/8-spd, Mineral Grey/Black (lease take over)