Containment cables. When old extension springs break, the springs and cables become heavy whips that damage cars and even injure people. To solve the whipping problem, manufacturers now offer containment cables that run through the center of side-mounted extension springs. If you have extension springs and don’t plan to replace your door, make sure the springs have these containment cables, or have a professional install them.
I hired Precision to fix one of my two garage doors. Barry was our technician and did a fantastic job. Not only was he punctual and friendly, he explained to us our options for service (which saved us some money), but he also went through a 101 on how to keep our doors properly lubricated and working properly. He finished the job very quickly, and was very polite. I would hire Precision again.
The electronics should also be inspected before or after investing in the cost of replacing the garage door panel to make sure your door will operate properly. The sensors prevent the door from closing on someone's foot or a pet. If they don't work, someone could be injured. Also check to make sure the door opener works, since you could otherwise be locked out of your garage.