Northern Tool offers the Mr. Heater Big Buddy Radiant Portable Heater, model no. MH18B, for $99.99. Coupon code "DEC183" cuts it to $79.99. Choose in-store pickup to avoid the $14.99 shipping fee. That's the lowest price we could find by $20. This propane heater features an output of 18,000 BTUs that can heat an area up to 400 square feet.