I bought this little NewAir heater (model G56) a couple of years ago for my garage workshop. I live in Minnesota, the land of subzero temps, where it does a fantastic job of getting my mostly insulated two-car attached garage from 40 to 60 degrees F in about 30 minutes. That’s plenty warm for my needs. You’ll need to have an electrician install a dedicated 30-amp, 240-volt circuit to power it. NewAir model 56 costs about $170 online. You can learn more and order at newair.com.