Kindly note it's the CNIPA who will examine whether the services fall within the scope of the main list or not. Please note there is no fixed standard on what services fall within the scope of "retail/wholesale services", but generally, it's said the services in sub-class 3503, such as "sales promotion for others; etc" should fall within the scope of "retail/wholesale services". If the serivces in sub-class 3503 are exactly the services of interest to client, client may consider this option.