va_landlord: how to select good agent? Very appreciate!!!!!

I am selecting an agent to put my house in MLS. I have no idea what kind of agent is good. I looks through the agent webpage find two are working in my area. A just has one list property, and price of property is high, B has 7 list property, and price of property is low. So select which one is better? A or B? I would give her half month rent if she brings tenant to sign the lease with me.