To manage properties effectively, ensure tenant satisfaction, maintain the property, and handle legal matters, hiring a property manager who is a member of the National Association of Residential Property Managers (NARPM) is an excellent choice.

why a 10% management fee could be a bargain for excellent property management services.

I live in New York.My initial research points to Detroit being an excellent cashflow market, almost too good!

I self managed and used an excel sheet to record all income and expenses. 

From there you have a great template to use and can set up a simple mail merge in excel for future deals.

Lay everything out in Excel or do you use an app? 

I am owner of my primary house, have excellent credentials, but I am unsatisfied with my passive income and potential to become owner in 20 years of a self financing house elsewhere. 

@Jonathan Greene this is excellent advice. 

at 7.5% interest I would suspect 11% is high unless you are an excellent manager of class C properties.

Excellent point.