Originally Posted by pseto
Was this a dealer who gave this quote and was it for both front/rear pads and rotors?
Many dealers will quote you MSRP for parts only and then discount it somewhat if you want them to do the work (although still cheaper to DIY). You may want to call the parts counter directly and see what price they give you or check online at getbmwparts.com.
At 42k, do you really need new rear rotors and pads? You can easily check it yourself.
agreed, likely pad changes are necessary, but all depends on how aggressively the brakes were used in 42k. I would get a up close inspection on rotor before swapping them. The rotors are the real cost driver in your quote.