Northern Tool offers the Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater for $358.99. Coupon code "254876" drops it to $338.99. Opt for in-store pickup to avoid the $38.99 shipping charge. That's $51 under last month's mention and the lowest price we could find by $70. It can be vented horizontally or vertically, and requires a venting kit.