My other tenant told me that numerous diff cars were there and people she has never seen before with out of state plates.

Your explanation was very clear!

This is an extremely watered down explanation of the business but this will definitely get you headed in the right direction.

Security deposit amountYou can find plenty of examples by searching for "tenant estoppel certificate doc" or exchange "doc" with "pdf" for more options.Here is an example and explanation: https://eforms.com/rental/esto...Some have a lot of legal jargon but this document does not need to be so detailed.

Because of that investors here in general are focusing on getting more bang for their buck with multi-family properties with higher rent potential.It's a pretty basic explanation, but it seems like we're in a textbook economics supply and demand exercise. 

I have been following Bigger Pockets for ~5 years, reading books, and following numerous forums.

He has done numerous commercial and residential real estate transactions, complex leases for me.

I would not be comfortable with the explanation -a really nice older guy who doesn’t need the money.

I suppose this could be a brand new agent, but even if that were true, he should still know better.Assuming that there's no rational explanation, I'd contact his broker and file a complaint with the local Board of Realtors, assuming that he's a member of NAR. 

Thanks Dave for the cogent and compete explanation.