How to set a thermostat, change fridge and a/c filter, garage door battery.

Would It be worth it to troubleshoot myself (look at thermostat, check breaker, look for overflow on the unit).

Each unit has a thermostat.  

According to my handyman all three of the thermostats I have in my single family rental property are no longer functioning and need to be replaced.

That's where I found my programmers, PAs, and db folks.

2 things by using a space heater the regular thermostat is not registering the proper temp in a room,, or by using the stove,, the stove is a fire hazard and by no means should be used for heating.. who's paying for the fuel to heat or run the stove.. just plain wasted energyGet rid of her, let her out of lease all, she's accident waiting to happen and write her up for not properly using appliances,, NO space heater should be used in your lease,, that alone unattended is a fire hazard.You will never satisfy her

You won’t have time to build furniture in the future, you need to focus on being the director of the circus.Install smart remote WiFi looks (LockState), NEST thermostat, smoke- and carbon monoxide detector, make the place business ready (printer, desk, etc.) and start an awesome looking listing on Airbnb for free.

do you need to upgrade the thermostats so your tenants can only raise the heat to a certain level?

Has anyone done the nest thermostats or ring door bells in a rental? 

The thermostat is firmly located in the living space of one unit, which means the second unit would not have control of or access to their heat source.