I installed a security system with ADT at my home in Unionville. It cost $1,000 for installation and I pay $50 per month for the next 3 years. I installed the service in September 2016, approximately 1 month later the system stopped working. I was then informed that a technician would not be able to come and check it out until 10 days later - REALLY? In addition, the salesman informed me that the installer would change the circuit board on installation - this was not done. Beware as well as the installer (Al - 416-320-2052) will not change the back-up battery if you have an existing system - you will need to ask for it. Finally, make sure that your system is not hard-wired into your electrical box - I found out when I was troubleshooting the fault with ADT technical support that the technician should have changed the circuit board with a different circuit board that could be plugged into an outlet instead of hardwiring it. The significance of this is that if there is a fault with the ADT equipment, an annoying beep will continue and you will not be able to turn the system off if it is hardwired into your electrical box because if you shut-off the circuit it is connected to, you will also shut off whatever else is on that circuit (in my case it is the internet for the entire house).
Support is terrible, the worst I have ever seen.
BEWARE!