If you hire a real estate company and they do a CMA make sure it includes:
1) Recently Sold comparable homes to yours
2) Active Homes comparable to yours (how long have they been on the market)
3) Under Contract homes comparable to yours (how long where they on the market)
4) Expired homes comparable to yours (homes that didn't sell, try to see why)
All this information is needed for you to make an informed decision. And if they have pictures, make sure you're looking at them.
Your #1 goal is to get the most amounts of buyers through your door. To do that you'll need to list and show better than the competition.
Make sure you have a Feedback Sheet for instant comments from buyers.
Also, make sure your home is listed on several sites and in print, especially if you've discounted the commission on the buying side. It's an ugly truth but some agents only search properties that offer the full 3%.