Once you have a handful of units, things become more stable because you gain a lot of experience and also when issues arise at one unit, the other units still carry the expenses.

Someone recommended not renewing to the family members as it can become an issue.

What calculator or resource do you like to use when analyzing larger properties or complexes (think 10 unit motels or inns).

Feel free to inquire about their staff qualifications if it's a larger organization.2.

The numbers work, but it seems the issue was me as a borrower.

Once we fix our side up and move in the property should be worth $200k-$250k (it was very undervalued at time of purchase).Why not take a larger loan initial on the purchase of the first duplex and lower your down payment, use the cash you have for the second purchase.  

I’ve been reading up on it as I have a water bill issue from before I bought the house.

That's one of many options.Once we figured out that the issue for us was more the lack of cash flow and less about the investment(we knew what we were going to spend either way) we paid 90% cash and that solved that problem. 

One issue I've run into is that some collection agencies don't report tenants to the credit reporting agency, which is a huge missed opportunity.

Just cause it's new construction, don't expect it to not have issues.