Is the deal still good if the agent is being difficult?

[Alan Kahn]

I'm looking to buy some investment property in another state.  Some of the properties I have looked at had the same agent.  In both times he was difficult.  Months of back and forth.  Still not under contract.  I'm getting close, but it is 2 steps forward an 1 back.  I think he is stalling in the hopes of finding a better deal from someone else. 

I don't want to reward bad behavior.  Do I keep 'playing the game' or do I walk away?