Chris has a few security systems with cameras and the alarm monitor (ADT) is obsoleting them. So he'll have to get new cameras for his system. Leo recommends decoupling the camera from the service and do the camera setup himself. The Nest cam works with Wi-Fi and they have their own cloud based storage. The cameras aren't cheap, but they're probably cheaper than ADT. Ring has one that's solar powered called the Stick Up cam. Leo also likes Axis.
(Disclaimer: Ring is a sponsor)