I was with ADT for quite a few years. Their sales team is one of the best. They can probably sell you air in your house and still sound reasonable. The nightmare begins when you need anything from them. Do not believe slogan 'it's good company" or 'oldest company on the market'. In case of security being oldest is not necessary good thing. When they installed my simple system (3 entry doors + patio door + single motion detector) for very reasonable $25/month with 3 year contract it was working few days, then alarm was going off every few days. Every time I called them to fix the "issue" they could not find it, while yet attempted to charge me for the call. Finally, one of the more experienced technicians discovered that original installer put screwed pair of wires inside of the duct. When warm air was going through, contact was naturally broken and alarm was going off. Once that was fixed, we lived in peace for several years unless I switched from Bell phone to VOIP. Strange code FC showed up on the panel, but I did not notice it as nobody called us about problem and system appeared to work ok (at least arm/disarm part) Finally, I got to the internet to check on that code and discovered that FC stands for "failure to communicate" which did not worry me much as sales person promised nothing can break ADT system. In case phone line is cut they will be alarmed right away. Well, that was not true. They don't. If you don't have phone line, they cannot monitor through traditional channels. I called ADT and they quickly acknowledged that there is no phone line, so they cannot monitor and even attempted to "apologize" for not calling me 2 months earlier (well, they did not forget to charge me!) Over phone they first asked if I want wireless "backup" for $200 and $45/month monitoring. When I refused, they offered $200 install of backup plus my current rate. While I still refused, we got into deadlock and I left ADT. Read reviews of others and you will be surprised to find stories about them out there. I won't look back as there are many young energetic companies out there that do job right for fraction of price.