He was trying to sell his house, and I has elderly and pregant women without A/C on 90+ days with high humidity, and they get priority with me. 

Fast forward to lousy tenant, who apparently didn't understand the concept of cracking a window to let the humidity out (no bath fan, remember 1950's).

Mine has a setting that turns it on/off at a certain humidity.

If you get alerts from your smart thermostat that the temp or humidity is out of range, you set you may need to have your HVAC unit serviced before it is a real problem.  

My Honeywell 9000 thermostats give me temp and humidity alerts.

As an investor I would shy far away from this if the GP had no experience in the market they are doing the homes.The other hurdles to overcome that I would be asking is, how do the 3d printed homes hold up in an area where temperatures and humidity are not stable?

We always leave the a/c on to regulate the temp and keep away humidity in the south. 

High property tax, high maintenance costs due to weather (AC running almost full year, hot and high humidity), high vacancy rate, high PM fees( first month rent as commission is a must, while other markets do not have first month commission at all), all makes Houston is a so-so market for rental business.Having said that, if that were me, I probably will get rid of half of bad ones and have a PM managing the rest of the half.

Possible other con is that it’s not a deadbolt but I find it pretty secureTheir customer service is actually pretty good, one of my locks broke in early usage and they send me a new one for free without hesitation, it ended up being the door itself needing adjustment not necessarily the lock, I’m in Michigan with hot and humid weather and cold freezing weather and no issues at all since then with any lockOne last thing/general tip: I keep one door of my rentals with regular locks and on a regular lockbox with back up keys in it, I’ve found it amazing in a pinch when you get that dreaded “my code isn’t working” and can’t get good internet service ect to change it at the time (most of the time it’s user error), also in cold weather states in older homes the locks can adjust and get stuck

You know the heat and air systems are constantly running even when the place is vacant to control humidity and/or reduce thermal expansion and contraction of inside elements (and avoiding frozen pipes in Wisconsin!).