As for the property structure, using an LLC offers liability protection, while a land trust provides privacy.

If I was the buyer's broker, I would have checked myself to protect my client.If they had, then they would have found out it was not a three family.

It can be done ethically, but you need safeguards to confirm mortgage & possibly property tax payments made on-time, as well as insurance with you protected.- Also, you need a legal way to take back the deed if buyer defaults!

A professional property manager should handle the heavy lifting, ensuring your investment is protected and profitable without adding stress to your plate.

Warren Buffet said the most important part of investing is to protect your principal. 

Additionally, involve a real estate attorney to ensure the transaction aligns with legal requirements and protects both parties’ interests.

The landlord should be named on the tenant's insurance policy for additional protection and to assist with tracking compliance.

Also any tips for automating this as much as possible and how to protect the property financially and property management would be appreciated.I ALMOST understand the rental arbitrage strategy if building a company scaling with say 30 + units and looking for high short term cash flow.  

Anything I need to be aware of or make sure they do for my protection?

When its included in a lease for real estate then the laws pertaining to residential rental security deposits in your state apply but when its separate you should have more leeway to get some additional deposit to protect you.