For all Kick Game sales there is a 3% payment processing fee, as well as a transaction fee that is dependent on the level of your seller account and the item you are selling. The transaction fee is taken from the final price of your sale. The more you sell on Kick Game, the higher your seller level will increase. With each level increase your transaction fee decreases.
Once a seller initially reaches a level by completing the required number of sales, the seller must continue to sell to maintain that level. Sales only count towards maintaining that seller level for one year.
For example, if a seller initially reaches level 3 by completing 30 sales, they then have one year from that date to sell 30 items OR reach £10,000 in sales to maintain the Level 3 standing. They'll need to continue to have 30 sales during a rolling 12-month period.
To see what level you are currently at and how many sales are needed to maintain that level, simply click "My Account" and check your seller level ranking.