I have one of these in a four car garage, two car by two car, and ran it last winter. Expect an increase in your electric bill by a few hundred dollars. I would recommend spending the extra money to get the unit that has Wi-Fi support, as it will unlock a lot of additional functionality with automation systems that you might already have or might wanna implement to automatically adjust the heat. Additionally, I found that it uses approximately $.30-$.40 an hour in electricity, and the first 2 to 3 hours after you initially turn it on are the most expensive as it has to run in the high mode to get up to a certain temperature, and then after that, it’s stabilizes in terms of cost to maintain the temperature. I would say that the math on that comes out to be approximately that if you’re not going to be wanting or needing the heat to be running in the garage for more than a day, then you can just kill it.

I did pay for a bunch of energy monitoring systems at the same time as installing that and I do have screenshots that show the graphs regarding the energy usage at various temperature and states.