So the main advantage of a DSCR in this case is just the fixed rate? 

In my experience strictly med buildings are generally developed in the same way as part of a campus or off the path a bit from the main retail corridor, so it really is only suited for that use. 

I think your last point about starting near infrastructure and moving backwards is very interesting.How much value do you put on a property being on a main vs side street?

The main objective is regulation and taxation.

Plex has some rough areas but mine are on the main road full of apartments for students.  

What is the main hang-up with financing, when it comes to adding bedrooms?

I have not seen any "main stream" versions of this just back country engineering but it's a solid concept and works well. 

Its certainly not "guaranteed return" - thats a word to always stay away from in real estate (in finance or even investing in general)high level - its because HMLs are going to be secured by the real estate, meaning in event of default, the lender can get the property to be made whole - somewhat trust is involved, but thats the main mechanism behind it

I think the main thing would be access to the books to make sure of the expenses.

That seems to be the main reason he left.