Originally Posted by Technic
You can always install the OEM 6FL retrofit yourself -or get some help- and save some real bucks... once installed then it will only need dealer programming.
Or, I think that you could end up paying slightly over half of the OEM 6FL retrofit $1200 dealer cost that you posted if you get the Dension Gateway 500 USB aftermarket module, and the installation would be way easier because it uses the OEM CD Changer connection: http://www.e90post.com/forums/showthread.php?t=84125
You might need to get an OEM CD Changer (you can borrow one from a good -a very
good friend is much better- friend with an E9x and save some money) as you will need the CD Changer physically installed in your car for programming. If your car already has a CD Changer then installation is virtually plug 'n play, as no programming will be needed: the Gateway will mimic a CD Changer, with full display and control interface thru your OEM HU or iDrive.
Installing a multimedia AV interface not? Plug&Play and cost around 200$