[header] How to prevent theft [title] Change your home's exterior door locks if you've recently moved in. [step] For the optimum security, your home needs to be outfitted with strong deadbolts and door locks to keep your stuff and your family safe. You can, as door locks are easy and inexpensive to replace. 
Once you do, always lock them and instruct anybody else you live with to always lock them. [substeps] It's possible that previous residents likely have kept a spare key, so it's a good idea to change the locks if you've just moved in, to help prevent theft.