Property value vs cash flow investing

[Vernon Brown]

Hi there!

I'm new to BP and real estate investing and I plan to purchase my first property (duplex or fourplex) within the next three months. In crunching the numbers on these properties, I have a few that are cash flow positive however I'm not sure if that takes into account the value of the property. How am I sure I am not paying too much. Just because I can clear $300+ hundred doesn't mean that the home is priced right! In addition, there are not many comps in the area (Atlanta) as many duplexes are sprinkled in primarily single family home neighborhoods. 

Any help on valuing these properties is appreciated

Thanks!