I called Royal Comfort for a/c and furnace maintenance. I was told that they charge $120 and clean the furnace, the evaporator coil and condenser. I was given a window of time the next day. The technician came an hour or so after the window. Cleaned the furnace and the electronic cleaner but said it was already clean (I had it cleaned 4 months before by a duct cleaner), did not clean the evaporator coil saying if the furnace area is clean there is no need to clean the evaporator coil. Opened the condenser panel, checked the freon pressure said needs freon -cost approx $300. I told him I had paid about that much the year previous and so there must be a leak that must be fixed. He said: difficult to find leak, said if you put in $150 worth of Freon it will last 6 mo to a year (but no guarantee). Charged $120 for furnace/ a/c cleaning (although did not clean the evaporator coil or the condenser) and $150 for freon.