What is the difference between going to a BMW dealer for a complete rear end brake job (cost is over $500)versus using a local brake shop? Does the dealer use different/better material? Does he have knowledge the local does not?
As for material…There’s no reason a local mechanic can’t buy their parts directly from BMW. There are many very very good aftermarket brake manufacturers. In fact BMW uses one of them. BMW does NOT make their own brakes.
As for labor…Brakes are NOT a very difficult job to do…It should be a lot cheaper for a good independent to do the work then the BMW dealer. Maybe even find a an independent who specializes in BMW.
Brake work is relatively simple. Any competent shop can do the job as well as the BMW dealership. No special knowledge is needed.
If you go to an independent you might discuss with the owner the quality of the parts (pads, rotors) he will use. You might choose to insist on good, better, best. Otherwise, you can expect equal results from either shop.
Dealer or shop… either or. However, you should insist on OEM friction material. Different friction can cause a different balance and upset the ABS and ESC programming.