I had a thief break into my home two years back. It happened one afternoon while I was hanging out with my friends. I live in a deserted place which is a kind stamping ground for these thieves. No one was home that day. I was really shocked to see my room when I was back. I called a few people who was standing out there but they did nothing. They didn’t even come in to see what has happened! But that was the first and last break in happened. I installed an alarm system the very next day and never had any problem after that.
By the way, what I have installed in my home is Alarmforce videorelay unit ( http://www.videorelay.com/videorelay-uses-details/?use=119 ). It’s been about an year since I installed and it’s giving me a complete peace of mind. It sends an email along with three pictures of whoever comes my home while I’m away.