I stay seven months in the rv so my house is rented or listed during that time.  

I would start by listening to Glen Sutherland's podcast called A Canadian Investing in the US - tons a great information for free.

It's imperative that these 3 parties stay in constant and clear communication with each other so that the ball isn't dropped. 

If you ever need any assistance related to long-term renting (rental analysis, trends, etc) feel free to reach out, I'd be happy to help!

My plan is to use the grant to purchase  a duplex  and live in one side for free or close to it.

You can use a free CRM (or low cost) for investing like HubSpot and not make a dent.

Living for free is the best!

All freshmen at WashU have to stay on the dorms for the first year, but after my first year my plan was to move off campus and put 3.5% down on small multifamily (2-4 units) and rent it out to the other students.

Are you thinking about staying in San Antonio for you next invesment?

Perhaps this agent and vendor are ready to be creative, as 3 years is a long time to carry property with no income.If you have any specific questions about owner financing, feel free to contact me, I've done a number of deals like this on the private market.