They are expensive despite incentives. I got them installed in a 2000sqft home but wanted to be less reliant on oil with the current pricing. They work great and I’ve run them down to 0 outside, but they are a different heat, doesn’t warm you as well as radiant heat IMO. They can run below 0 but there is a cut off where it costs more in electricity to run that low versus my oil prices. My house was partly reinsulated with spray foam after irene so it’s “mostly” good… still have more work to do but probably better than most really old houses.

All that said i luckily have very reliable electricity and usually supplement heat with a wood stove versus my oil boiler as much as i can. If you are putting in a generator because of unreliable electricity, not sure dumping your heating on it is worth it.

Like i mentioned above a new boiler or retrofit will probably be less than half an install depending on what credits you qualify for with the new programs in 2023 and your generator wouldn’t need to be as big either!