There is a cheap way to do it:
A) shop around at your local salvage yard and haggle with them or buy on ebay.
B) buy all other parts from tischer
C) install everything yourself.
My total cost was $400, would have been $300 if I didnt get the FZD, which I'm pretty sure you dont need if you get a TCU that has already been programmed (mine FZD is gray in a tan car, so I know for a fact the FZD isnt made for my car so theres no point of it. The Assist worked, but after I got off the phone with them, they somehow disabled my Assist. I tried to push the button again and it said "call error"
Sorry for the confusion, but if you go the tischer route you are looking at a FZD (the price recently went up to almost $350 I think), REMAN TCU, loudspeaker, possibly a MIC, and dealer programming. ~1100 seems about right, I'd go the cheaper route if you are willing to wait a couple months.
Dealer said if I wanted to enable the Assist it would cost 2 hours of labor, so I opted out.
Originally Posted by enforcerman
You NEED the FZD (thats the overhead console w/ the bmw assist button). You can not do the retrofit without it. There is no cheap way to retrofit bluetooth into your car.
Thats my experience. Total bluetooth retrofit was in the 1100 range.