Especially the days when you discover that big capex like a roof being blow off (happened 2 years ago), some tweakers climbed up on the roof and gutted the A/C (did two of those in the last 12 months), an evap cooler leaked for so long that the drywall on the ceiling of the kids bedroom caved in (last year), the hot water heater blew a hose and a major leak went unnoticed for 10 hours flooding the hall, kitchen and living room (dealing with that now), the tenant smelled gas outside, the gas company came and shut off the gas because the underground pipe is corroded AND also discovered that the water heater is not venting properly so it got red tagged (just dealt with that last month) or the time the tenant "invited" a homeless guy over, he moved in, then called his other homeless buddy up and he parked his crappy RV with his entire family living in it in the driveway.

At least the weather will be a little cooler in a few months when you move.

I like cooler tones in bedrooms because it's more restful.

Going to the tankless units helped with keeping the studios cooler in the summer.As a side note, you need to verify that you have a large enough supply line running into your building. 

I'm considering finding homes that just have swamp coolers and putting in small duct air systems for their energy savings and ability to help them compete with newer builds. 

You can find all the limits here at https://entp.hud.gov/idapp/html/hicost1.cfm I can put you in touch with a great local loan broker who can tell you whats available for a low money down conventional if you wish.

The AC maintenance is minimal with "swamp coolers" that we have here in NM, and my husband does that, so it doesn't add much expense, just new pads each year.  

The rental side (we’re living in the other side but may be moving soon) also has a through-wall cooler that also does not work.

The rental side (we’re living in the other side but may be moving soon) also has a through-wall cooler that also does not work.

Basements are generally cooler so pipes are exposed to the freezing temperatures much more than the other parts of the property.