Okay, so you've played through the whole game of Metro 2033 and feel like you've been missing out on something. Well, did you go after the achievements? If not, here's a tutorial on how to add some points to your gamerscore. The name of this achievement is called the Wheeler-Dealer. It's an easy to get achievement and requires you to buy and sell shotgun ammo over and over again until the achievement is unlocked. So good luck and enjoy!