When you swap out your old dial for a smart thermostat, the biggest change is that your heat stops running when you leave the house. The installation takes about thirty minutes if your wiring is straightforward, though you should check your wall first to see if you need a C-wire adapter. Late summer and early fall are the best times to buy and install one before heating season kicks in and contractors get busy.
We are looking at about $250 for a solid unit. Before you buy, check if your local utility company offers a rebate or a discount on specific models. It pays to look at a couple of different retailers to compare prices rather than grabbing the first one you see online.
Just remember that 0% intro APR for 15 months on purchases and balance transfers is a deadline, not free money. If you still have a balance left when those 15 months are up, standard interest kicks in on the remaining amount.