When my preferred vendor went over he found that the "HVAC TECH TENANT" installed a Programable thermostat (not recommended in Rentals because some tenants don't know how to use them), and shorted the 24v circuit to ground thermostat circuit to ground.  

My thought on the water heater is that it either has a leak or broken thermostat making it run continuously.

Pretty much just installing curtain rods, changing the thermostat, and painting.

Although I am going with this guy for this job, I am always looking for more properties and can work with newer people if I can save some costs.I got the below pricing for a completely new system including new ductwork2 ton 14 seer AC Unit Franklin (by amana)Gas Furnace 80% 40.000 buts to 60.Evaporator coil concrete slabrefrigerant copper lines and insulation low voltage wiring for thermostat and condenser. 5 to 7 Supply air ducts boots and grill.2 return intakes grills under the unitDig. thermostat Suppl plenum Miscellaneous material to complete job10 years warranty equipment 1 year labor warranty.

I've read a good rule of thumb is 10W per sqft, but the convection heater says it should handle this room size, and I'm sure the tenant will appreciate the lower electricity bill.Considering:Convection Heater (400W): https://www.wayfair.com/home-improvement/pdp/amazeheater-llc-amaze-heater-dual-400-watt-electric-convection-panel-heater-amhr1002.htmlIn-Wall Heater with fan (and built-in thermostat) (1500W) : https://www.homedepot.com/p/Cadet-EnergyPlus-1600-Watt-120-240-Volt-In-Wall-Electric-Wall-Heater-in-White-CEC163TW/206750445

With separate electric heat and thermostat in each room there is no issue with the tenant not having heat when all they have to do is pay their electric bill and use the thermostat accordingly.

They had thermostats on them, but the thermostats didn't seem to control the units.

Your thermostat would likely go down to 50 degrees. 

If it is using a wall mounted thermostat this is preferable.

One boiler and all the units were zoned with separate controls and individual thermostats in each unit.