Typically you work with one agent here in the US. Find an agent you click with, who is knowledgable and listens to your wants and needs. An agent should also be honest and tell you whether or not your needs and wants are obtainable in the price range you're looking in.
I would speak to at least 3 agents to interview them, ask to speak to past clients for recommendations. You can also tell a lot about an agents knowledge by browsing their website.