What is his hourly rate and how long did he tell you it will take to do everything?
If it will take him a day his hourly rate will be $355.18
If it will take him two days his hourly rate will be $177.58
and If it takes him three days his hourly rate is $118.39
If he's not a dealer his rate seems HIGH.
Also what type of guarantee will he provide for the work performed? BMW guarantee their work for 2 years unlimited mileage.