When creating my LLC I was not allowed to use a PO Box and had to use my personal home address.

You should be just fine with the properties in your personal name and an umbrella insurance policy.

We (my wife and I) decided instead of buying a new home and renting our primary we would buy an investment property with the funds instead and just sit tight in our current home in the short term.

I always recommend that anyone getting started attend in person meet ups.

I would definetly consult with an attorney before and ask if you would be able to get these people out of your property in you needed.If may just be easier to steer clear and try to find a good applicant with a SSN#Or, if there is a company that employs a lot of people without a SSN# you could reach out to the company, ask if they need housing for there employees, and then rent to the company instead of the person.

Person A has the renter's insurance while Person B does not, but Person B's belongings is "mostly covered" by Person A's Renter's Insurance.

When done properly, a series LLC gives members protection from personal liabilities arising from multiple properties or operations without having the extra expenses of multiple LLCs.Series LLC also known as master LLC provides liability protection across multiple LLC entities.

Have the family pay you with their funds and then pay themselves back with his money. 

Can I use my personal credit cards for business expenses and somehow expense it to my LLC bank account?

I am looking for cashflow  - no really flip and fix market .Looking for person/agent/team   who is expert in the market can guide in securing the first  two deal .I am open to consider the single family house and multifamily apartment building