ADT Security System question

[Brett Lee]

I am buying a house for our family. The owner has an ADT security system in the house. He explained that the reason because of his drug addict son. Based on that we are definitely wanting to have some level of security. My wondering is if anyone has ever had luck hooking another security system up to their ADT system or if people have had good experiences with ADT? Definitely looking for decent security monitoring at an affordable price. Any insights for advice would be greatly appreciated