When you get to that open house he or she will show you all the amenities of that home but at the same time they are trying to sell themselves. Don’t do your interview at the open house but if he or she looks like someone you can work with take their card and by all means give them your name, phone number, and email. First you want to see how long it takes them to contact you and second you want to interview them later.
What are you looking for in a Realtor? First of all you want one that knows the area and the market in that area. I once had a friend that worked only one specific area in a Metro Area. She also worked with her mother who both lived in that area and she had also grown up in that area. Riding with her down the street she could literally point at every home and tell you the name of the people that lived there, when they moved in and what they purchased that house for and what that home should sell for now in the current market. Now your chances of finding someone that knowledgeable is extremely rare and in all my time in Real Estate I have never meet anyone that knew an area that well. But that is what I mean when I say a Realtor should know an area.