Every accessible door and operable window should be protected. All glass windows should be protected with some sort of shock/audio detector. Windows can also be protected using alarm screens instead of contacts and shock/audio detectors. Obviously in a three story residence, the windows on the third floor cannot be opened by normal means; screens, vibration sensors or audio detectors should be sufficient if the windows are kept locked. Rather than contacting these third floor windows, the money could be spent on additional interior protection or other security features like fire detection. However, if you would feel unsafe with these windows uncontacted, contact them. It's your security and your peace of mind.

Garage overhead doors are a special case. A lot of people get these doors contacted and then pay extra to have the door bypassed automatically when the garage door opener is used. Since the only way to open these doors is by using the garage door opener, they are paying for the door to be protected and then paying more for it to be unprotected. Don't spend money to protect a door and then spend more to bypass the protection every time the door is used. Spend your money on additional protection or added features.

If there is no automatic opener, a contact can be useful protection on a garage door. If there is an automatic opener and you wish to protect a boat or trailer stored in the garage, there are devices designed to attach to the boat or trailer.