The tenant probably kept it under their hat, precisely because they have seen the kind of toxic reactions which appeared in a flood at the beginning of this discussion.

Will I know with precision the FMV of my investment 5yrs, 10yrs, 20yrs down the road?  

That is precisely what I'd like to do and, frankly, what I enjoy doing.

Would we - or more precisely a U.S.A. entity owned by us - be eligible to purchase this property or is it only available to a "natural" person who happens to be a U.S.A. citizen?

Know the laws of the state where the property is located for a more precise understanding of the legal documents.

You might be able to draw these up yourself if you're good at that sort of thing, but make sure everything is measured precisely, because I accidentally submitted the wrong square footage of a garage we were permitting as livable (with my own drawing), and that mistake cost me a lot of time and extra fees.You can reach out to the county and ask for their records of your property, with a list of everything that's been permitted, but it usually takes longer than 30 days to receive the records.

I would like to expand my holding over the next few years; I am considering purchasing more units - possibly in Charlotte but could be anywhere in NC or outside the state - depending on the deals.I've looked around on the forum for some specific answers and find some that are close, but not precisely this situation. 

I wouldn't call $500,000 cheap - I use sub $200,000 as my parameter for "cheap" and if I'm not in a severely negative cash flow (-$100 to -$150 at most for first 2 years at current interest rates) but it's hard to tell since I can't predict precisely how many tenant turnovers, capital expenses, how much my property taxes/insurance will go up, repairs I would have on a renovated Class C Midwest property that's 100 years old over 10 year time span.

I am thinking that I would find out precisely how each lender wants to see the loan package put together, and guide my buyer in doing so.

But this is precisely why real estate has evolved to become the team sport that it is today.