Rough numbers may a general guideline to CYA, but to your privacy and second point. What data is gathered, stored, for how long and shared with who? What are

Rough numbers may a general guideline to CYA, but to your privacy and second point. What data is gathered, stored, for how long and shared with who? What are your options if the system goes offline? I have a Nest Thermostat that I bought before Google acquired Nest, which raises another general issue of your device having an evolving T&C to use.