Steering Wheel Vibrations. Brakes squeaking. Loud clicking when breaking at low speedsl

Only at a certain speed (40-50)mph does the steering wheel begin to vibrate until I am out of the certain speed. As well my front brakes I beleive are squeaking a lot. Makes a clicking\snapping sound when I press on the brakes.I took my car to a mechanic who speacialized in the exact mercedes models & told me it was something to do with brake supports? Wanted to charge me 1300$. Can I just get a decent guess\response please? Thank you