I know it told us to change the battery at 6 months but we still have not had to. I keep waiting for the time when I go out and it wont open. We put it in the side of a steel garage. So that was the hardest part cutting the steel. After that it went in fairly easy. I emailed service one time when I held the button and could not get it to work right. If you read the directions youll find out that is a setting some people want. Anyway he answered within 15 minutes to tell me what to do. All in all I think this was a good buy,