I hate to break this to you but the 7 series are the ones that break down the most. If i were you i would sell that before any goes wrong with it in your care. BMW's are allergic to powersteering fluid, the control arm bushings were bad designs, and the rear shocks tended to leak. Not to bring you down, just a heads up. A brake and rotor job with sensors on that car will probably run you about six hundred and fifty dollars.