I don’t know how big your house is but $14,000 in 2004 got AC for my duplex. I just had them put in central AC and leave the hot water boiler for the heat. They put the unit in the attic and then it was easier to run ducts to every room on the second floor and then ducts through the bedroom closets to the first floor. easier than I though and greatly improved quality of life and electrical expense. Removing the window units got me my windows back and no more noise. Besides quality of life the AC helped get me a better price for my house when I sold it.