Although the housing market slowdown, supply-chain disruptions and inflationary pressures have been creating hurdles for the industry players, companies like Watsco, Inc., Comfort Systems USA, Inc. and AAON, Inc. have been gaining from maintenance, monitoring and repairing services, along with prudent cost-management practices. FIX and AAON, Inc. AAON. AAON: Based in Tulsa, OK, AAON engineers, manufactures and markets air conditioning, as well as heating equipment.