No more fumbling for keys in the dark or worrying if you remembered to lock up when you left. A smart keyless entry lock changes your daily routine immediately, and swapping out the hardware usually takes less than an hour. Late fall is the best time to do it because retailer discounts peak during holiday sales and home pros often have wider availability before winter sets in.
If you pick up a solid lock and pay someone to put it in, expect a total bill around $250. Spreading that cost out lets you upgrade your home security without taking a lump-sum hit to your checking account.
Remember that a 0% intro period is a strict deadline, not free money. If you carry any remaining balance past those 18 months, standard interest rates kick in on whatever is left, turning a cheap upgrade into an expensive one.