Clear fee structure. When attracting new sellers, the marketplace must provide them with a clear formula for calculating brokerage commission. Sellers need to understand what percentage of the sale they may expect. Complicated calculations like "Commission 2.5% on the sale of each item, an additional 1.5% on the sale of more than 5 units to the same buyer, and 1% for the sale of the entire assortment within a month" are likely to turn off the seller. Whereas a fixed rate, i.e., a one-time charge for the sale of goods, will become the strength of the marketplace.