I am thinking about having a heat pump installed for my single-wide mobile home. I'm not sure what the installed cost will be and have not gotten estimates yet. The forced air furnace works OK and I supplement that with an electric oil burner portable heater so the FA heat only comes on 2 or 3 times a day. Still, my electric bill from Puget Sound Energy hit $300 a month last winter and I do not want to repeat that. I can afford to pay cash for a heat pump system but I'm not sure if the cost is justifiable. I don't plan on moving for years so I look at it as an investment. I replaced all of my windows with Milgard Style Lines last year and that has been a big improvement. I had a guy from PSE come out to seal all of my registers and he crawled underneath and inspected the ducting and said that it was in fine shape. He also told me that my FA furnace was pretty good. I live in Kenmore, WA which is pretty close to Seattle and also is just off of Lake Washington so the days can get fairly chilly in the cooler months.