not sure squealing brakes are a sign they need replacing, BMW doesnt put the churp stick on pads, BMW's have a brake pad sensor that should come on when the pads reach a min thickness. if you have the tools and the knowledge, take the wheels off and look at the pad thickness, there could be another issue why the pads are squealing. And yes you would be 100 percent correct! the BMW Palace will charge you a S**T Load to do a brake job, Pads will be in the 150-200 dollar range(just a guess) and they also have a mandatory replace the rotors too. I would stay away from ebay buying break pads and rotors, several BMW aftermarket sites that others have used to get brake pads and rotors and dont forget the pad sensor too!