"You can put it on a window so you can't raise or slide it at all," he said.
Some people hammer a nail into an old window frame for the same effect, but Lang said that's a safety hazard. You can't get out in the event of fire. Lang said you need to make sure the window lock has a thumb screw you can turn in the event of emergency.
Your garage door
As for your garage, that hanging emergency cord you pull if the power goes out is a target for any burglar with a coat hanger. They can reach in, grab it and unlock the door.
But it costs you nothing to secure it.
"Tie the cord up -- or use a sandwich bag tie -- so you can't grab it and put it up through the garage door," Lang said.
That's another fix for less than $1.
Who is at the door?
If you don't have a window right next to your front door, it is frightening to hear a knock after dark.