Cold weather has a way of finding every weak spot in a home. A dusty filter, a drafty door, a forgotten outdoor faucet, or a thermostat set a little too high can all show up on your winter bills. The good news is that getting ready for winter doesn’t have to mean spending a lot. Some of the best prep takes an hour, a few basic supplies, and a little attention before the first real cold snap hits. One of the easiest and most overlooked jobs is changing the filter in your heati