who does window tinting and whats the aveage price for a 4 door sedan?

price 100 and change

done by many local shops

make sure to get a warranty

Average price for tinting is 100-150 dollars. But there are some things to remember. For example if you live say in PA but are near the Jersey boarder you could go to Freesbie Enterprises(in Newton, Sussex County) and have Tommy do your windows. While his work will exceed your expectations there is one more bonus. He'll give you 5% on all the windows and 8" down the shield. Just an example about leaving the home town area and getting someone who knows their stuff to do the work. Also a good tint shop will usually keep your car for the day if not over night to guarantee that their work is good. And last but not least this bit that other people put about a warranty maybe on the tint it's self but the job sorry at least not 80% of the time. Please remember tint can get you in trouble in some states even though they sell it there check you laws or be brave. I know my tint breaks the law but I also don't give the cops a reason to bother me. Best of luck.