How much will game stop give me for these games on the x-box 360?

Dead space 2, Duke nukem forever, minecraft, MIB alien crisis, the walking dead survival instinct, portal 2, halo wars, halo reach, halo anniversary combat evolved, and dead rising 2

ShadowOps is wrong. You could probably get up to $50+ depending on the condition of the games and the original packaging. If it's never been opened, you could probably get more than $50. I wouldn't recommend selling Portal 2 or Minecraft, though (those are my 2 favorite games xD)