The service fee(commission) of each order is 5% of the item value plus 5CNY.
For example, if you are going to buy an item of price 130CNY and shipping of 12CNY, FreeShoppingChina.CN will charge service fee of 130x5%+5=11.5CNY. So totally, you will need to pay 130+12+11.5=153.5CNY.
If you are having coupons from FreeShoppingChina.CN, the coupons can be used to deduct either item value, shipping or service fee. There is no limitation.