RBTR is his primary strategy in DFW and can probably share a few tips/recommendations with you. 

I do have some balloon notes on a few properties, and I’m wondering if banks might see refinancing as risky since my primary income now comes from my rentals? 

I strongly advise you to get your primary residence taken care of FIRST.

I know SC is steep for non-primary residents.  

The parent must file a gift tax return annually, and any remaining balance is included in the estate.If the home was your primary residence for at least 2 of the last 5 years, you may exclude up to $250,000 ($500,000 if married filing jointly) of capital gains from taxes.

Initially, I was focused on multifamily properties, but after doing more research and considering that I will be making Florida my primary residence, I believe that house hacking or short-term rentals (STR) may be the ideal route for me.i still will own my Southern California home; shift it to secondary.  

We would likely do a cashout refi on our primary residence for rehab costs.

Most areas have never updated their zoning bylaws to allow solar to be a primary use.

Our standard language states:In the event that Tenants decide they no longer want to live together, ___________ will be considered the primary Tenant to make decisions about modifying or terminating tenancy.

Hopefully in just a few years the cash flow can help fund your Primary rehab and enlargement.