How much is a colt peacemaker .22 serial 6175609 worth?

Just as automobiles every single gun is a different story, depending upon condition, etc. If the gun is nice and has both 22lr and 22 mag cylinders and they are both nice then the gun should bring a minimum of $400. If there is just one cylinder then probally around $300, if the case colors are still intact then this just helps the selling to the gun as much as the price.