She was studying to get her CA Broker’s License which would fully legitimize us, and allow us to manage funds on behalf of the homeowner’s and have ownership of the listings and reservations.

You can do a trial and see if bank feeds connect, if it does, I would then recommend using it over QBO.One of my client that just started in development is short on funds so Xero was the only best option and they are using a local bank so we couldn't connect and a lot of manual entries. 

I did not read the rules around security deposits. you may be allowed to use those funds and still file a small claims action for any remainder, but I can't imagine that it would be worth it if you have at least one month's rent in security deposit. 

If you really want to supplement your income, my thought would be to take out a HE loan (or some other 2nd position loan) and use that to fund a down payment on a property.

This can give you the flexibility to fund your flip without the restrictions of a HELOC.

Stessa for the rentals, Monarch for the other accounts (IRAs, brokerage accounts, cash, etc.)

They take their portion of the housing voucher like clockwork and my funds are tied up in their system.

For example, promises of guaranteed funding for deals were not upheld in my case.3.

Few people have no clue what is or how it works, I was just reading today that the cannabis growers that will be trading BILLIONS of dollars in CA, cannot deposit those funds in traditional banks, therefore; many will be using Bitcoins and other digital currency. 

If interest rates fall later, refinancing again might require you to bring extra funds to the table, which could impact your overall investment strategy.