Problem:
In the traditional "Black Market" Third Party Gaming item trading website the seller submits an item and when its sold the third party gets a commission out of the sale.
When trading gaming items on the blockchain Minting" the seller has to pay blockchain fees in order to submit that item to the blockchain, and that's quite problematic because the seller incurs fees even if the item doesn't sell. So the seller looses money even if the item doesn't sell !!!
Think of it, as if a seller pays for shipping costs on amazon even if the item doesn't sell.

Solution:
The seller offers the gaming item on a market, after the buyers decides to purchase the item it gets blockchenized and the fees are deducted.