What questions to ask them
Before they come to you, you should go to their offic and see how the place is kept, are properties well advertised etc, are the staff well mannered etc. then ask them some of the following questions when they come to your house.
1. What have you sold in the last 6 months?
2. What experience do you have with sales in your area/locality?
3. What service do you provide for the fee charged, look for examples of sales brochure, newspaper ads, and what signage is used.
Once you enquire about the fee, feel free to haggle, but be aware of what the going rate in your area is and I wouldn't use the current climate as a reason for a lower fee, if anything its a reason for a higher fee.
Ask for forthright opinions on your property and what it should sell at. Your gut feeling as to whether you are dealing with someone that is good at their job should kick in. They should be well presented, personable and (appear) honest.
don't let the fee be your guide to choosing an agent.