You have to know the market before you build a plan and I don't think this market supports your intended plan.

Found it through a broker on the market.

I am an experienced investor and unexpectely find myself managing a duplex myself and wondering if there is a small landlord (aka inexpensive) simple solution for marketing, background checks and lease creation that markets on zillow? 

I am targeting Cincinnati, OH as potential first market because I grew up not far from there and have at least some connections.

The high appreciation market will be the higher cash flow market over the hold.  

With future leases, as soon as it is determined there is nonrenewal, you start marketing that floorplan.  

Engage an investor-focused realtor/broker in your preferred market (this is not a residential realtor) and start 'tire kicking' the market and properties that fit your criteria.

And that number depends on you, your market, your property and your goals.

This strategic flip leveraged our market expertise and efficient deal structuring to achieve a quick and profitable transaction.

I’m not familiar with those markets, but I would suggest finding some meetups and attending as many as you can.