Refer to your lease about key return and also your state law.We have in our leases:Tenant must return all keys and access devices provided by the Landlord when surrendering the property.

The serial number of the device is registered with their email, so a factory reset wouldn't help. 

These devices allow tenants to set automatic schedules for heating and cooling, which helps reduce energy usage and extends the life of the HVAC system.

Look at some of the smart devices you can install at your properties - if you are self-managing this is really important!

You can put devices to check where it's coming from - also do you have a PM ?

They also pair with most price optimization sites super easily and you can control a lot of the homes smart devices.

(I had to remove the link for this is paste, but you can find it this with a quick search)*****Count the number of loan mods out there, and the number of properties with missed payments, and the number of loans sold to hedge funds, the current unaffordability of houses and whatever other devices they have used to disguise the true situation and you have a problem.

They setup a few devices that take air readings both inside and outside the home. 

Sometimes the opportunities are bug-out packs and water filtration devices and bullets.

While many of the requirements are "good" in theory, like backflow prevention devices on hose bibs, to me it is unfair if they don't require this on every house vs just rentals.While some people think it adds a level of safety or "upgrade" to the community, to me it is a cost and that cost will be passed on to the tenants, who could by choice decide to live in a house without the checklist vs living in one that requires the checklist.To me it is a violation of the 4th Amendment....illegal search and seizure.