They did negotiate the balance down for the previous owners debt and I had the previous owner sign a notarized document that they would pay it off or go to court.

The county keeps telling me to sign a notarized release form stating that the information will not be used for commercial purposes.How can i get around this?

If they are not registered, have a notarized authorization form that they could sign documents pertaining to your project.

We plan to have a notarized joint venture agreement between our LLCs and our friend's LLC.

I did not have a notarized contract with the land lord because I personally knew her and thought she was a stand up person.

They ask for a letter of hardship, the current lease that my tenants have including a WET SIGNATURE (even though we E-sign everything), and a notarized copy of the loan packet. 

And yes, we have a notarized loan agreement. 

Do we establish a notarized contract and nothing more?

I could require the owner of said property to submit a utility bill (scan or snail mail) before their listing is approved - but those can be photo shopped.Same goes for a notarized copy of ownership.

You are on the right track but you might want to talk to an attorney to cover yourself, you might also consider requiring a notarized signature on the note.