I had an old ADT system in my house but had not used it in several years.
Contacted Bulwark through a Yelp review and am very happy with them. They upgraded my old system and added new sensors.
Its been 4 years now and everything is still working great and the monitoring system keeps an eye on it.
Would highly recommend them! Plus they are local and would much prefer to support someone local than a large chain where the $$ goes elsewhere!