In my area, Zillow uses our MLS so any member buyer broker can set up an auto search that automatically sends you property with x days on market, then new ones come as they reach that criteria, or most other criteria you prefer.

Do you think I have to start with 2-5 units or just analyze the numbers and try to scale up to more doors (which is my goal at this point).

You would find it beneficial to achieving your goals. 

A diverse set of locales comprise the 20 markets withthe highest availability rates and leasing times for small industrial spaces.The four largest Texas markets, Austin, Dallas-Fort Worth, Houston and SanAntonio, all rank in this group.However, most of these 20 markets with higheravailability rates and longer leasing timelines than most locales still havelimited inventories of small industrial spaces available for lease.

Message me at your convenience and we can set something up.  

My goal is to get on with one of the big Brokerages that sells trophy ranch's and get back into land sales whence I started..

All that being stated I am planning to refinance again and developing a game plan to obtain another property with the goal in mind to rent my current property.

I am confused as to how to set the monthly rent.

Smart buyers understand the value of a Buyer's agent and it certainly is not just to open doors.  95% of my clients are out of state investors purchasing in a market that they do not know nor live in, they count on me to walk the property, access repairs, provide comps and short term rental numbers, arrange and be present for inspections, as well as my ability to assist them getting their short term rental set up for them long distance.  

What was the goal for you when you bought the property and how did that goal align with what the turnkey provider told you about it?