I'm doing a build out of my shed thats 20x20ft and is reasonably well insulated. I'm located in northern New England and will need to run some type of heating unit to keep the building at proper temps. I was thinking that about 10,000 btu of heat should cover the room's needs, I'm hoping somebody could recommend a good propane wall hung heater that comes with a thermostat so I can keep the room dialed in the low 70's. I see tons of them out there for a couple hundo that you just set on "low" and "high", but with day/night temp swings of 20 degrees I need something with a brain. Any help is appreciated guys, thank you