The only thing I can think of right now was selling the original Final Fantasy, manual, map, and all, when I was only about four years old. I couldn't figure out how the hell to play the game, neither could my brother. It was just too frustrating, and Garland actually managed to knock us all down, several times. Not knowing how it could be played, manual or not, we sold it. Sure, I own it for the NES now, but I just have the game, and not anything else. This is why I'm not selling anything that I currently have. I probably never will, unless finances become truly desperate.