Duplexes cash flow better, have less risk, AND EASIER TO MANAGE compared to a SFH.  

This will help guide your decision opposed to investing somewhere for a novel reason.for example for me it was cash flow, price to rent ratio, land lord tenant laws and availability of multi-families(Just to name a few). 

The amount of cash flow on a home will of course be contingent on the down payment.

Ohio is a great market to be invested into as you can still find positive cash flow (aka the 1% rule) and tons of appreciation here!

It’s also worth considering a multi-family property for your first deal since it can help with cash flow.

I guess my only other option is to add padlocks onto the cash boxes on top of the regular keyed entry.

You could simply offer them a small cash equivalent for the “interest” when you return their security deposit…rather than bothering to open an interest-bearing account, if you’re worried about it.

Our cash on cash return is essentially infinite as we make money on the delta between the yield of the discounted note that we purchase and the interest rate we pay to our passive private capital partners. 

A 20% down payment will allow you to have a positive cash flow, even using conservative projections and a property management company.

What you’re suggesting is not cash flow, it’s return of principle, giving her her own money back  If she sells with your deal.