The idle speed is not adjustable on the car in question, if the idle speed is too high chances are that there is a vacuum leak. If the shop spent time chasing vacuum leak to fix the idle situation you have no leg to stand on.
Why don't you post a copy of the repair order instead of naming the shop in question. For all I know there is another side to this story. If the charges were so outrageous and unfair call your credit card company and your case hase merit they will do a chargeback.
I guess it's better to bash the shop in question without letting them defend themselves right?
