My headlight went out in my car, how much to replace it?

APPROX 120.00

My 2008 MKZ's left low beam light went out . I purchased another low beam bulb and replaced it. That did not work. Luckily it was still under warranty. The Thornhill group in Chapmanville WV had to replace the whole headlight assembly. Cost 1,200.00. That is ridiuclous.