Trade runs on the air? nope I'm not that obvious lol, and as for VPN you have to google, if you are looking for decent no lagging ones they are most likely paid.
I did received your message, if you go under the "sent" section you can see all your messages sent.
I use a VPN for my alt account, and I do use both Derp and the Mod, I use them for Treasure Hunting, Automatic bid set for my items, Mailbox anywhere, Pack-Finder, etc.
