My main concerns are splitting bills, mail, and AC temp (only 1 AC unit).

If you mandate that the A/C be on from June-September that is fine, but if it was set to "my home" temperatures it would never turn on because of the temp would never drop below.

The owner keeps the temp very cool and the guys had the doors / windows open because there were in and out all day long.

I have never heard that hotel room prices is correlated to housing price.If they are correlated, and if I were a hotel owner like Steve Wynn, I could have manipulated the housing market and stock market easily by reducing or raising room rate any date.  

Tenant left the hose connected to the spigot over the winter (live in Midwest where freezing temps occur during Winter). 

I have started looking at Tempe, Mesa , Chandler and Scottsdale. 

These have a special jumper that you can move, set the max temp, then move the jumper back.

Please realize these statements are easily manipulated and usually are manipulated.

It takes away from property owners rights Rent control is a ham-handed manipulation of the marketplace, which will inhibit development and investment, and have the exact opposite result intended.

Doing this will provide each room with their own comfort options, but each room will need their own remote to control the air handle temp.