Document it.

You would need to consult the Denver zoning guidelines (can be found online) which is a 1000 page plus document to see if an Additional Dwelling Unit (ADU) is allowed on that property based on it's current zoning.

In Calif, we use the forms provided by the RE agent - - unless you are attempting a FSBO or wholesaling transaction in which case you are on your own for all documents. 

The seller must check their loan documents to see if a wrap loan is allowed. 

Hiring a lawyer to draft or review the document is totally up to you.  

It would be solely for convenience and would also allow me to have my personal address not listed on public records documents and leases.

Doesn't the agent have a fiduciary responsibility to their client (buyer in this case) regardless of any documentation or signed agreement? 

Obviously you will want to have documentation to show all the monies paid so when the TB goes to finance you have proof of everything as well. 

We compare signatures from the release form with the signed exchange documents.

Let me explain, if he is a RE Investor, he may need someone who can run some errands such as documents, purchasing things in a hardware store etc.