I need to replace it with a thermostat.

They had a small plumbing issue that I had to call a plumber for, and just this week they asked me to replace the thermostat with a programmable one so they don't have to run the A/C all day in the summer and I have to find a handyman to install one.

I have even seen thermostats that can be controlled remotely so to keep tabs on the AC/Heat.

In my future real estate plans, I want to make my flips as environmentally friendly as possible, and that includes smart technologies (likes Nest thermostats and smoke alarms).

I know locally there are rebates for HW heaters above 67% efficiency, furnaces above 96% efficient, programmable thermostats, pipe insulation and others but most appear to be SFH.

A couple of days later, I gave them each a sweater and suggested they stop overruling the program in the thermostat :)

If each unit is plumbed as a seperate zone controlled by their own thermostat , you may be able to measure their usage by a flow meter .

They tried to sell us a separate fce & a/c but I have a great HVAC guy & we efficiently used the existing system by splitting it with separate thermostats & solenoid run dampers to direct flow as required.

The heat is a gas boiler with a landlord thermostat (does not go above 71 degrees).

If you have these properties in less desirable locations, in my opinion electric baseboard in each room with a thermostat for each room works best.