An alternative to the Nest and Honeywell systems is the Professional Bayweb system. No they don't advertise, they don't have to. The home based system costs about $328.00 including humidity monitoring, and no cost wifi access for life.
I have used them for home, vacation houses and commercial buildings. Some systems are over 12 years old and still working perfectly. I get almost instant notification of power and internet outages and restorations along with equipment malfunction. Want to know if your housekeeper is actually doing there job? Just add a dry contact to the door and you will receive instant notification.
https://bayweb.com/
https://store.bayweb.com/