If in northern US, they suggest you combine your heat pump with a furnace to cover, keeping the house warm under 32f. After building an addition in 2008, I went with a early 2 stage design heat pump in Massachusetts (at that time only single stage available and would not work under 32f) While is was OK, had problems holding the house at 68f when temp went into single digits not to mention an $800-$1000, electric bill for December to January. Ended up going back to oil.

If you have gas available, it's more reliable than oil.

We now use a pellet stove to heat an 1800 sqft cape to 72f, with the oil as backup when not home. This year, we used around 70 gallons of oil since September. Pellets cost us around $350 per ton, and I expect to run 3.5 tons by May. Est savings over oil of $2500.

https://www.pelletheat.org/compare-fuel-costs