I live in a 1000sqft 1940s townhouse with 1978 heating/air and am looking to replace it. I have received a few estimates all with different brands and a significant price differential. I understand Carrier is one of the best and the price reflects that. I will not likely live here more then 5 years and my funds are not limitless. I can not likely afford to go with the Carrier. My other choices are Luxaire or Heil. Any comments on which is better or which one should cost more based on quality?