I would go with an independent agent as they will have a ton more options as far as insurance companies for you.

With each one I have a engagement contract that clearly spells out their responsibilities and independence.

We inspected every unit, performed a lease audit, had an inspector test the systems, and hired an engineer to study the land improvements and utilities.

There are generally 2 routes to take: hire him as an employee (of which he will pay withholding tax, thus lowering his income), or hiring him as an independent contractor (of which he will be able to write-off anything he does for you.) 

I would be careful to document your initial valuations well because if anyone was ever audited it could be looked at just because of the closeness of relationship.  

Our daughter is grown and fully independent and we are now looking towards retirement.

Have you tried to talk to any of the independent mortgage brokers to see what they can find for you at all?

Any bank with any sort of underwriting standards is going to ask, already know, and independently verify the answers to the most of the above questions, so you might as well answer them up front and bring the bank documentation of your analysis.

I would like to be financially independent and become a part-time real estate investor in the states! 

That way you can be an independent broker and not have to work for anyone.