I've never paid to have a trailer moved and I'm uncertain what the cost of utilities from the city hooked up would be so I was just wondering what people's experience has been with that. 

You should therefore be responsible for the heating of that tank which then you should see an increase in your utility bill ..If it is indeed them using the water you're going to have to charge them. 

Only one apartment can be powering the heater if the utilities are separate.

As I mentioned, we utilize the lower half of our home for Airbnb.

Lastly, if time flexibility is your top priority, I would look into brokers that doesn't rely on traditional offices and practices, but rather take a more mobile approach to their broker model as office hours can be very limiting in terms of how you are able to utilize your own time. 

My mortgage, utilities (shared), maintenance reserves, and water would be $1,000 per month. 

With this high level back drop, I've been scouring online resources to better understand the relationship between operating and holding LLCs and am trying to understand the basic mechanics of how they entities are utilized in the conduct of the BRRRR strategy.  

I would price out the construction costs on both intentions and then make a decision and consider the maintenance costs of either type if you plan on keeping it long term.Its location and demand in that area should effect your decision too as well as site accessibility,  land research, the land contour plus how you might use any extra space or the current zoning allowance or the utilities that exist.

I was wondering if anyone would be interested in building a professional relationship and utilizing Direct Mailing for buying opportunities.

Never had this issue before when purchasing other properties to not let us test utilities.