All depends what you want. We got a quote for a new Lennox Merit 3T 14 seer single stage compressor with a variable speed air handler from one company for $5800 installed. Getting a 18 seer Trane XL18i two speed compressor and TEM6 variable speed air handler from another for $9950 including a complete vent cleaning. Replacing a 21 year old 14 seer Lennox Elite system. When I had it installed 21 years ago it was less than $5K installed. This is in western Frederick county.