Advanced Heating & Air Conditioning came and checked out our furnace. It seemed to be having problems and my husband thought it was going to blow up! They took a look at it and it turned out it was just that the tabs were broken on the cover for the furnace. They put some screws in and everything was OK. It only cost around $90 for the visit, which I thought was fair. I called them in the morning and they came out the same day. I've had them out before and would definitely work with them again. They're just very friendly people.