I also recommend you educate them on the damage that can be caused by a leaking toilet, dripping faucet, faulty thermostat, etc. 

There is an additional trip charge of $50.00 for non-scheduled service calls.In signing this document I (we) agree upon and accept the above charges upon move-out or when necessary.Date Executed: _______________ Date Executed: ________________ Tenant Signature(s): Landlord or Property Manager Signature: ____________________________ ______________________________________________________________ Plumbing Replace kitchen faucet $150.00 Replace bathroom faucet $105.00 Replace faucet handle $20.00 Replace faucet aerator $10.50 Replace shower head $27.00 Replace toilet $175.00 Replace toilet seat $25.00 Locks Replace key (door or mailbox) $10.00 Replace cylindrical door lock $35.00 Replace deadbolt lock $25.00 Windows and Window Coverings Replace window pane (single) $75.00 Replace window pane (double) $125.00 Replace mini blind $20.00 Rescreen window screen $25.00 Replace window screen and frame $50.00 Miscellaneous Replace refrigerator shelf $35.00 Replace stove/oven knob $20.00 Replace plastic countertop $325.00 Replace mirror $55.00 Replace medicine cabinet $75.00 Replace towel bar $25.00 Replace shower curtain rod $25.00 Replace shower curtain & rings $18.00 Replace shower/tub enclosure $350.00 Replace thermostat $80.00 Replace fire extinguisher $35.00 Remove junk and debris (per area) $35.00 Replace smoke detector $40.00 Replace combo detector/alarm $50.00 Replace alarm battery (per battery) $3.00 Replace drop ceiling tile $10.00 Replace wireless doorbell $35.00 Replace portable window screen $15.00

Same with garbage disposals, sewers, digital thermostats, electronic locks, garage door openers, etc.3.

My question mainly is can I even tell the tenants what they "have" to keep the thermostat at going forward?

But when the thermostats start to go out.

The guy in the middle unit can't figure out how to run his manual Honeywell thermostat.

It has never failed or need batteries replaced.I do use wifi thermostats, wifi water heater and exterior cameras.

3)Furnace did not operate when thermostat set, have evaluated, no heat to house upon arrival.Possibly due to thermostat problem but unknown.

It was turnkey in that I could've turned it into a rental after close but I chose to make some upgrades like the arcade games, making the home smarter with smart lock/thermostat, etc.I closed in late Jan and went live the first week of March.

If it’s an electric water heater and it appears in good shape, you can simply replace the heating elements and thermostats.