eBay charges fees to list your item on the site. The cost depends on total of fees calculated based on the starting price, selling price, selling format, optional listing upgrades, category, and site. The eBay fee pages have tables to help you figure out how much it will cost you to sell your item.

Insertion Fee - If you want to sell on item on eBay, you create a listing using the Sell Your Item form. When you list an item, you are charged an Insertion Fee for the listing. The Insertion Fee is based on what you decide is the Starting Price of your item or the Reserve Price if one is included. For example, you want to sell your Sony camera. You list it with a Starting Price of $60.00. The Insertion Fee would be $2.00 (from the table on the fee page).

Final Value Fee - If the item sells, you are charged a Final Value Fee. The Final Value Fee is based on the final amount the item sells for. The Final Value Fee does not include shipping costs. For example, your item sells for $153.00. Your Final Value Fee would be $6.67. This is calculated as follows: $2.19 (.0875 times $25.00) plus $4.48 (.0325 times $128.00) for a total of $6.67.

Listing upgrades - Additionally, you may want to add a subtitle or an extra picture to your listing, a charge would be added for each listing upgrade. The charges also depend on the category and format you list in.

When you sell an item, you can review your fees on the Sell Your Item form before you submit your listing.

Спасибо :) Мне стыдно, но я никогда условий для продавцов не читала - я только покупаю :)
То есть, процента 4 в среднем, ага.