I feel like a couple pieces are missing to scale my business.  

A good bookkeeper and CPA can be worth the investment as you scale.

I have a sub to like question along the same lines.I own a STR that is performing well (30% COCR) and I want to scale my business.My parents own a few properties in cash.

We would just get comfortable and loving our job and then a merger would happen or some knucklehead at the top with no real lending background would come up with some "great idea" and shake things up.

That hurdle will likely be a major roadblock to really scaling your portfolio, as I don't know any successful investors that have avoided debt entirely.

doing new build rent refinance and repeat im looking for any advice to help build affordable houseing and for scaling 

I don't know I will be able scale and make money.

House Hacking with GSE-subsidized loans is definitely the top way to start and do this but you max out on this pretty quickly when you are seriously about scaling. 

I am looking to scale my business and am leveraging an investor (my parents) to fund my down payment for 5 % interest on a 10 year loan.

That cash is worth much more to me now in the scaling stage.