A good smart thermostat with room sensors is meant to last a decade, so you want to buy the right setup once instead of replacing a cheap model in two years. These devices manage your home climate and cut heating bills by learning your routine.
New models drop in the fall, which means Black Friday is prime time to grab last year's hardware at a discount while keeping all the same core features.
That intro window is a hard deadline, not free money, and any remaining balance left over when it ends will trigger standard interest charges on what you bought.