I use Simplisafe. Easy to self-install. Monitors for temp, water, smoke and security. I like it because it doesn't require a land line or WiFi. It connects via its own internal cellular chip. It doesn't allow me to change the temp. For that I use Nest. I also use a cheap (lt $100) set of wifi cameras focused on a few key things in the house; sump pump, water shutoff valve, furnace panel.
http://simplisafe.com/home-protection