Good rental investment areas in and around Dallas city

[Frank Quattro]

I am looking to invest in rental property in Dallas. 

My goal is good rental income, easy to rent out property (i.e good demand), not older than 2000 year and Max price 340K (townhomes preferred).

What are some good places that meet this criteria ?

I was told University park, Irving, Dallas, Plano are few cities to look at. Which one do you suggest is better ?