Be sure and check and replace your furnace filters every 3 months. If you own pets perhaps change every 2 months. This is a very simple process, simply check the size of filter, then go to local hardware(Ace), big box store(Lowe's, Home Depot, Menards) many larger grocery stores and Walmart carry the filters. Be careful to insert the way the air is to flow and you are done.
In winter time it is recommended that you remove the hose from the outdoor faucet and let the water drain from hose. Keep the hose disconnected from faucet all winter.
If you own a lawn mower, it's a good time to remove blade and have it sharpened, clean the air filter on mower and change oil. If gas is left in tank add an additive like Sta-Bil to the gas.
If on a well water and have a water softener be sure and check the salt levels weekly and move the salt on bottom around to avoid small cavities forming.
Keep in mind we are just the caretakers of the home/condo.