Well, he didn't notice corroded coils which are leaking chemicals and mold that are extremely obvious even to the untrained eye when peeling the panel off. 

@James WiseCat’s claw, trim nailer, power tools, circular saw, all 50 lbs of it. checked it in.

Well, it was not, the unit is VERY old, the coil is leaking (directly into the electric furnace, but that's another story, it too is about 30 years old).

For small spaces, you can't get a small enough (in terms of BTU) multi-zone unit and what happens is one unit receives refrigerant even when not running if the other is running, which due to the cold of the evap coil causes it to condensate and ultimately causes constant problems with drainage.Also, look for a mini-split where you can connect an external thermostat and configure the head unit to shut off when the set point is reached.

We raised their rent from $500 to $780 & they now pay for the bi-annual cleaning/servicing of the evap coil on the furnace because the smoke/nicotine residue is so heavy.

When it really needs a jackhammer, power nailers, and generators.

However, if the furnace is 20+ years old and likely to need to be replaced soon, I'll go ahead and replace the unit and get a new unit with air (evaporated coil and condenser).

I need the whole deal, coil, condenser, furnace, and a return added.  

By climate control I mean structure would be insulated and foundation would include heating coils to eliminate the moisture.Thanks

Evaporator coils can also become clogged over a long period, also reducing air flow and adversely affecting the system.