Power Inverters

Hey guys quick question. I was playing with my new TT the other night and wanted to see what would and wouldn’t work off AC hookups. Obviously the AC and microwave don’t work (and any of the 120vac outlets) but what wasn’t obvious was the furnace blower also didn’t work any more. Being gas heat, I was kinda surprised the furnace didn’t run the blower motor off 12 VDC. Anyways that got me thinking, is it common practice to add a second battery and add something along the lines of a power inverter to recreate that 120 vac for stuff like mainly furnace blower, 120 vac for chargers, etc? What inverter to people use? I want to install one but don’t know if it’s common practice or not. What are your experiences ? Thanks guys.