It would be a great idea if you can afford it. I had a little 3000 watt which would power my refrigerator or the window unit in my bedroom but not both.
It would not even begin to power my central air/heat.
My radio and small 12 volt TV did much better than I had thought. I had two Stanley 1000 watt jump starters which included all kinds of power takeoffs. When one would get low I would simply plug it into my car as I drove out to Geneva, Al to get gas, etc.
Have not checked the prices. I see alot of them next to houses.