For example, there are some administrative legal fees I paid early on (notably: Having a lawyer draft up the PSA, and setting up my LLC which holds the title).If I ever get audited, what will the be looking for?

Company/employer contributions are made when taxes and books are confirmed to be accurate and total maximum amounts are verified by CPA and administrator. 

Just compare costs and the administrative differences. 

Starting an S corp now will just increase your administrative burden and tax prep fees. 

The fee they pay covers the administrative costs of updating leases and tenant ledgers as well as re-keying the property, to ensure the departed roommate does not have access to the unit once the termination goes into effect.  

We're not looking for a bank to be the administrator, but simply hold our trust account.

I have multiple mortgages, banking accounts, credit cards, brokerage accounts, crypto currency accounts, crowd funding accounts, employee 401k, self directed ira, employee stock plan administrator, shares in a small-town bank, I feel like I could go forever.

(Especially in a Trump administration where wild cards are everywhere). 

Regardless of this, you must "manage the servicer" of the note as well as complete all business administration tasks as Chris noted above.  

I do not like this program because... we still have the administrative task of following up to make sure the tenant does in fact put utilities in their name and sometimes the forget!