100k is what I am asking, Its not a crazy price for him in the least bit.
He is one of the rarest pets and maybe the best pet for battles in the game.
You can buy his loot card for around $230 last I checked.
Every time you deliver a killing blow to any mob or player of your level range, the Soul-Trader will visually siphon the soul out of the dead enemy in an eruption of purple electric bolts which connect from the pet to the dead body. This works in raids and battlegrounds. This effect happens no matter how far the mob is from your pet, if it grants experience or honor and the Soul-Trader is currently summoned, he will siphon its soul.
Every time he siphons a soul, he rewards you with a token which can be used to purchase various vanity items that he sells. Did I mention that this pet is also a vendor? He sells equippable Soul-Trader gear that you can wear and several vanity items and elixirs He will also switch from his running/teleporting animation to a walking animation when you are RP walking.