heres what i bought. I went electric because i hate breathing in fumes while my shop is closed up. Just for example on its ability. My shop is 2600 sq. ft with 20 foot ceilings and no insulation. At about 40-50 degrees here in the bay area it will take the nip out of the air in about 30 min. Im positive it would make a shop 1000 sq ft or so really toasty in not time and its not very loud which is nice too. they are pricey new but i got mine on craigslist for a couple hundred bucks used and it works great!
http://www.everyspaceheater.com/Fost...A-FRO1005.html