If they're doing it right, they will protect your property, income, time, and sanity.

A plumbing cabinet, electrical cabinet, protective gear drawer, flooring cabinet, hardware, tools, etc.

@Jonathan Santiago@Dave FosterI'd agree to keep your short term activities separate from your long term activities as a matter of asset protection / liability. 

It's easier and better protection.

If I own my properties via an investment holding company that owns subsidiaries that take title to my properties can I do a property cash out refinance and pay the proceeds to the holding company tax free to buy more properties that are fully owned by the holding company to protect each of my properties from each other.Would an LLC or Corporation structure be preferred for this to work?

If it happens to be a friend or relative who believes in your and knows you, then you might get a great interest rate, but you still need to protect them with a mortgage and/or a deed of trust AND closed at a title company or Atty office.

Your personal assets are protected from any issues that could arise from investing in real estate. 

A Payroll Protection Plan Loan is an SBA Loan for existing businesses.

What type of legal entity would be best for us all to be protected?

I know that it's better to set an LLC for every rental property, considering that the main purpose is asset protection, but I also read that you could have more than one under the same LLC as long as they have low equity.