Sounds like a lot of money but you're paying for convenience.
Alternative is to get your hands dirty and DIY.
Spend $200 on a decent tool kit, buy the parts online from pelicanparts or similar - and spend an afternoon with this set of instructions.
http://www.xoutpost.com/articles/x5/...andle-fix.html
If you can put together an ikea bookshelf, I reckon you could do this.
Worst case scenario, you get stuck - drive the car to your mechanic with the parts needed, and you're down a few bucks on tools.
I recommend something like this, cost me $170 (Stanley 132 Piece Kit)- I do all my own work on my cars; haven't been to a mechanic in 10+ years....all using this tool kit. Aside from speciality tools for some jobs, it's all you should need. EDIT: for this job though I would also recommend a trim removal tool, because you don't want to muck up those clips and get rattly trim - plus, now that you own a BMW it's worth investing in a decent Torx bit set because they're everywhere on these things.
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2005 3.0d Sport - Sapphire Black
Engine : Bluefin Superchip Tune,
Wheels & Sus: Style 168s (10.5s all round), H&R RDA Spacers, Bilstein B12, Eibach 40mm drop, Whiteline RSB
Exterior: Le Mans flares, 4.6is kit F&R
Interior: Dynavin N6, Blackvue DR650 dash cams
My Build Thread: http://www.xoutpost.com/bmw-sav-foru...run-sheet.html