I know some states require a broker's license to be able to legally manage properties owned by other people. 

The question is would this be a legal use, as long as I have proper documentation, or would this be seen as intermingling funds?

Since rent wasn't paid, you're in default on your lease and can be taken to court for back rent and related fees.When an owner declares bankruptcy, the court has a decide how to pay the debts and which assets will be liquidated.

You want to have good and profitable experience not headaches and insurmountable debt experience.

She has agreed not to break the lease and have subletters, can we legally evict?

Or, go further into debt trying to take care of these issues... which doesn't help either because then you are now paying down that debt (credit card or what have you) and your mortgage/other expenses. 

He agreed but since he was busy on the job we didn't really have time to discuss it further.So of course, one option would be for me to just be his private money guy and structure it as a debt deal, but I'd really rather get a little more skin in the game and partner with him. 

So the only question is, does the Market Rent for that location and Type of Unit cover the HOA, plus Debt Service, plus whatever other Expenses need to be paid..Because if it doesn't, the Landlord is in for a world of hurt!.

What does that mean - it means that you can take all the classes you need to be a successful investor, manager, financial planner, ethics and legal reasoning etc with the only penalty being you get a grade less than desired and of course you are spending for college.

@TIM HUGHES in nearly every case it is best to pay down debt first.