Another observation that I've made is that properties are in high demand near places of worship like church, masjids, etc. 

Some of Berlin's most attractive feature are: Relatively low rents (compared to Paris, London, Brussels, Madrid)Low real estate prices (idem)Comparatively low living costsAmple supply of parks, lakesCultural amenity: Museum, squares, historical sites, churches, etc.

I bet there is not vent (supply air) in the room and you are not getting enough air movement with the door shut. 

In my case, the unit was released to me in 2 days since it was a pretty open and shut case.  

-Supply will probably always be there:  Unlike a business, you don't have to worry about the University shutting down.

Should I take the time to set up each unit with its own hot water, and additionally install shut offs for each unit in the basement where only i have access....so if the unit doesnt pay water,,,on their own...i can get the notice from city and turn off as they would any other SFR rental i have in town...Thanks in advance for your input.

All permits in order before you begin work, you don't want some inspector to shut you down then have to wait 2 weeks for his next appointment!

Maybe he is involved in church, but it was odd at how he threw it out.He ends up showing me his bank account on his phone - $1500 in it.

There was another but I understand they got sued and shut it down.In some severe cases, more so when I still rented single family houses before I started doing everything shared housing, I would post a youtube video indexing the tenant so others would be warned.  

I loved DR so much I used to teach his classes at my church.