well at least both parties are both happy. i have heard don't buy second hand, thats an option, but not one that i would consider as a default setting. i have bought most of my equipment second hand, and never had a problem. as you say you are new to the game, maybe find out the facts first, get second opinion, the stress caused to yourself and the other party could have been cancelled. difficult i know, as you had made a decision that something was faulty. lessons to be learned, wisdom found, hopefully you can pass that lesson learned on to the next generation of shooter.