If I found a 4 unit property to purchase as my personal residence using an FHA loan could I still get the deal financed if I needed a relative to co-sign for me?

The concept of a Credit Union is the membership shares some common interest (aka a co-op). 

My son is a co-owner of the house (to build his credit, give him a vested reason to keep things reasonably decent, and tax advantages of owner-occupancy), so I went with individual rental agreements with his roommates.  

I am a co-owner in NXT Level Properties, LLC.  

I thought about agreeing to that if she's able to get a co-signer.

When I first got involved in the industry in early 2014 there were platforms using a co-investment model where they invested funds alongside the crowd.  

As a few months gone buy and finding out a co worker of mine is a licensed Real Estate Agent.

Hello, A co-worker is purchasing a SFR in her hometown of Potosi, WI in preparation for retiring from the military.

My math is something like this: 169K purchase + $1500 closing costs on purchase, $2000 holding (utilities/insurance), I'm assuming a hard money loan so ~$20K in loan fees, $39,000 rehab, $2700 resale title costs, $7K to pay an agent a co-op on resale I assume?

Wondering if there's a way to structure it so that the partner receives an agreed upon ROI for a short-term investment, but isn't a co-signer on the loan.