Does that include utility service to the house, a driveway, septic and well? 

As for my personal experience, at one point I was under contract for them to build a house for my portfolio as a LTR. 

Specifically, I’d love to hear about best practices for managing shared spaces, screening tenants, and setting up house rules.Additionally, I plan to split the utilities among the tenants—any advice on how to handle this efficiently would be greatly appreciated!

Cost segregation utilizes the MACRS approach.

Now purchasing a home with cash is always good b/c obviously cash is king but also I think the part you might've missed is that, the money your utilizing on these home's won't actually be yours, but the banks or whatever institution you used to fix the home or make its value worth more.

You can also tell her to call the utility company about the best way to save, as turning off heat and on is not efficient having to run longer blasting out cold air as opposed to leaving it set at a lower temp. :)

Estimated about $25,000 including utility hookups.  

HOW TO SHARE UTILITIES 101You have a property with two or more units and the utility meters are shared.

Utilize tools like BiggerPockets for resources and calculators, and consider creating a simple spreadsheet to track property details, budgets, and timelines.

So all in all, the investment seems solid to me, and this is not my first rodeo, as they say.As for the risks associated with the SBLOC, I minimize those by only utilizing a portion of the LOC so that even if the market drops another, lets say 30%, the risk of margin call is slim.