There is one constant when your dealing with World of Warcraft. Every interaction you have with someone is a possible chance to sell. Whether it's a direct sale request from a guild member, or with a complete stranger from Trade Chat. Each time you contact someone, the opportunity to sell or invest is there.
One of these places is Heroic Dungeons. Heroic Dungeons are where players are getting geared up for raiding. When a piece drops that they need and win, that is the best opportunity to find out if they need an enhancement. If it's a healing piece and your a tailor, have a good healing thread ready to sell. Leatherworkers can have armor patches all ready to sell in a moments notice. Jewelcrafters should have their blanks ready to cut and sell to the winner.
This can also be looked at a good opportunity for advertisement. Cutting a deal with a player in a Heroic can advertise your business just as good as barking in trade chat. Many players like to work with one or two players instead of having to run around finding the character enhancements for their toons.
The other point of this is to have knowledge of what is going to be the best for that player. A tailor will fit a piece of wardrobe for a new customer each time. An excellent tailor will know when to crease and fold that same wardrobe to make it stunning. Your knowledge base on what the best DPS item or Healing item can reward you with added gold in the long term.
Every contact is a potential sale. Every piece of knowledge puts you one step closer to your ultimate Gold Goblin Goal.
Good Luck and Good Hunting
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