When your tenant stops paying and communicating, who will knock on the door to see if they still live there?

It also has a 2 car garage that was closed in and we will probably close off the door into the main house and finish it into a 1br 1bth.

You do the math.Plus all the the exterior projects: new siding, new roof, building out eave returns and soffit overhangs to fix the poor curb appeal, un-converting the attached garage, driveway, retaining walls, the detached garage, 144 truckloads of fill to create a front yard, landscaping... 

.- We can better control what's on our master key system- EVERY lock at a property is opened with one key (well, maybe not the garage car-door)!

For example, the garage door must be remotely controlled so:The property manager can remotely open it to allow delivery and service people access.Access to the garage will be through an app on the tenant’s phone, no clickers or digital keypads to reprogram.

I helped a client purchase an SFH fixer with a detached garage.

Can you recommend a management software for managing 100+ doors I tried Cozy.

Conversely, On homes I have wanted to expand,  I have removed closets from bedrooms in order to label these as studies or offices, so that I could build additions that are labelled "bedrooms" (customized to my needs),  in order to avoid the requirements of expanding a 2 car garage to a 3 car garage (a local requirement when building beyond 4 bedrooms).  

Except that this spring there's going to be a cabin built next door.

Fun fact: best ROI in the annual Cost vs Value report is a garage door.