I did my alternator when I hit about 100K on the car.
Parts $850
Labor $free (self installed)

Easy job but requires a good bit of parts taken out.


Here is one of my DIY's you can use to get to the point where you remove the serpentine belt. Afterwards it's a tight fit but it all works.
http://www.xoutpost.com/bmw-sav-foru...-n62-4-8l.html