Here's an ideal PM contract: The two keys are: The PM is incentivized to make you money, not charge high fees, and is contractually bound to provide reporting that you can understand in a timely manner. 

I would highly encourage paying a GC to walk deals out the gate, have them give a scope of work so you can see what items costs.

I have personally purchased large apartment complexes from REITs and know how poorly some of them manage their properties. 

I prefer Section 8 tenants to low income cash paying tenants but there is a damn good reason why many landlords won't put voucher holders in high end properties.

I guess my question is this: is the very low cash flow (due to my low down-payment and high interest) going to improve?

We have a pretty good Tenant who is moving from one apartment unit to another.

And in those events prices can rise dramatically!

Our home state, TX, has really high property tax which is see as a big disadvantage.

It is somewhat complex to try to explain on a forum, but at a high level, you (aka GP) and your family member (aka LP) would agree on how much the 2 of you would put in for the amount of equity needed (usually expressed as a %).

I only have 4 SFR with sec 8 but I’d highly recommend it.