Calculating commissions on Trendyol is a critical step in determining the true profitability of marketplace sales. The Tecof approach evaluates the selling price, product cost, shipping costs and category-specific commission rate together. This makes it possible to see not only the turnover but also the net amount remaining per order. The aim is to manage pricing decisions based on data rather than intuition, to identify margin losses early during campaign periods, and to safeguard sustainable growth.