Color for color (shaders, armor, weapons, ships, sparrows or whatever has a color) Raid gear/weapons for raid gear/weapons Bounty weapon for bounty weapon Can also add glimmer/marks/motes to the above trades for a better incentive. 1 for 1 material exchange ONE open exchange per account (psn or live) ONCE per week. After that you can do an additional trade once per reset per account with someone you have been on a fireteam with at least ten hours. In addition to that you may also have an end of Raid or Nightfall trade with someone you completed it with (2 minute window) once per reset and only with the rewards earned on that run. This would severely hamper PayPal sales and prevent loot farming schemes. I believe this is the best way to go and the best way to prevent cash for gear sales.