This list is not exhaustive, but can provide a starting point.

Security/Privacy

Ensure there are solid working locks on all windows and doors and use them! All should always lock the door behind them and always carry a key. Would-be thieves go door-to-door until they find an unlocked door.

Use opaque blinds or curtains on your rooms--they not only help contain heat/block drafts in winter, they make it impossible for thieves to see in to identify where computers, TVs, etc. are placed, and how many people are home.

Arrange for a frequent housecheck if you are away for an extended period. Get a trusted friend or neighbour to bring in the mail, make sure the heat's on in the winter and ensure that no break-in has occurred.

Make a descriptive inventory of all your possessions. Keep it in a safe place, i.e., something that is not likely to be stolen! In the event of fire, theft, or disagreement over ownership--you can support your claim.

Outdoors

Ask the landlord to trim back any shrubbery or tree branches that obscure vision and behind which bad people could hide. When you are coming home late at night you want clear sightlines to your porch and doorway.

If there is not an outside light over your entranceway, ask the landlord to install one. Replace the bulb as necessary.

Ask the landlord to install a motion-sensitive light for the driveway or backyard so you aren't exiting your car in the dark.

Fire Concerns

Make sure you have adequate and functioning smoke detectors; install fresh batteries when you move in. A fire extinguisher is a good idea; keep it properly charged.

All routes of escape should be accessible at all times, so don't block entranceways with bikes or fire escapes with storm windows and BBQs. If you have a fire escape, make sure it is in good shape. Check to see that a prowler cannot gain access to the fire escape from the ground.

When the House is Empty-Winter and Summer

Leave the heat on--at 55F or 13C--when you are away in the winter to prevent pipes from freezing. Leave a full oil tank if your house will be empty for any amount of time; if the tank runs dry in a cold spell, the pipes can freeze and burst in only a few hours.

In summer, check with the landlord to make sure no sump pump or dehumidifier must be left running if you are going to turn off the electricity. Leave fridges defrosted and their doors propped open--to prevent ruining them with mildew-- if you unplug them.