You can also request a security deposit for extra peace of mind. 

my RE income from my rentals is semi-passive of course... so less active than W2 but more active than dividends or social security.

Does anyone know what officially gets recorded with the county when a mortgage is transferred?

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

I dont allow tenants to move in without first month rent and security deposit paid by cashier check .

Hate to hear the guy claimed to be a Marine, whether it’s true or not, I have come to realization no matter the person you have to trust your gut about a person and this article only secures those feelings.

https://fox59.com/news/officials-confirm-two-dead-in-tenness...This is a state fire code on sleeping more than 12.

Also, what’s been your biggest challenge when it comes to securing the funds you need?

Quote from @Gary Bonds: Any best practices when attempting to secure business funding from a bank, in the form of a loan or credit?

I did not read the rules around security deposits. you may be allowed to use those funds and still file a small claims action for any remainder, but I can't imagine that it would be worth it if you have at least one month's rent in security deposit.