@Ryan Phelps, I'd gladly take a free 25% equity stake to lend private funds, but as @Curt Davis mentions, you'd still need to pay by the entirety of the loan I gave.Both parties should draw up the loan documents using an attorney. 

Whenever you are purchasing a deed restricted property that is within an HOA you should review all the HOA documents including covenants, financials, rules and regulations to ensure you understand what you are getting into. 

In terms of managing finances, I use my property management platform to document everything.

Set up my LLC and various other legal documents for me.

ie how to track income/expenses, budget for future repairs, keep track of all important tax documents, current leases, etc..

Like I said, I’m bad about stopping and taking time to document, so wanted to do that to have something to look back on.

My misconceptions are that 1) the lease is a lawful binding document.

Document your progress and more unforeseen opportunities will come. 

This lesson has already been learned by others in your area, so go get that wisdom and don't make their mistakes.You need to start documenting your rental criteria as soon as possible.

Gina, it's not an official document and therefore there's no format for it.