Yeah, $1200 is way too high. A detailed estimate wiil tell you what else, if anything they're going to do. Maybe they found other trouble codes. I agree with smazur that it takes ten minutes to replace a MAF sensor, however the car then needs to be driven a few miles and the self adaptation needs to be re-checked to verify the problem is fixed. Vacuum leaks, fuel injectors, O2 sensors, and even neglected air filters can all cause problems that mimic MAF's. It takes a decent tech a lot longer than ten minutes to make sure the car won't come back with the same complaint.