If you want to stick to wholesellers / MLS while concentrating on flipping, you should aim to try to find something with maybe $10k more spread than this which will be very difficult but not impossible.  

I concentrate on Denton specifically though. 

I am concentrating on the Westmoreland County Pa area for now.  

You need to find more money, that is what you will need to concentrate your efforts on.

He concentrates on small mixed use properties, a store with one or two apartments above.

We have decided to concentrate on the school systems of North Hunterdon HS and Hunterdon Central HS, people are willing to pay the higher prices and property taxes for those school systems.

@Marcus Brown - I don't worry on concentrating where cash buyers are buying because in reality if you have a good deal someone will buy it.

Where New Jersey has no concentrated Landlord Association by Area.Let me know if you have any questions.RegardsJoe Scorese

Perhaps in Phoenix and Florida where there are large concentration of retirees. 

In the interim concentrate on your career path to increase your income.