When I quit World of Warcraft a few years back, I was looking to sell my account in order to make a little money and ensure I never attempted to play again. Gamepal only made one of those goals happen:
As soon as you are done changing your account information, telling them how to pay you, etc, you begin recieving emails from "Blizzard" asking you to confirm you are the original owner of the account by giving away sensitive information, and threatening to suspend or freeze the account if information is not provided. It directs you to a fake account login screen and goes downhill from there. Do not trust them.
Unfortunately for me at the time, there were no bad reviews for the site, just the fake ones that their owners undoubtedly pumped out. So I will be the first to warn everyone to STAY AWAY FROM THIS SITE. I'm sure all of their buying opportunities are just as illegitimate as their selling opportunities, and this goes for all games they claim to do business with, not just World of Warcraft.