Opencart extension

Hello , I want some one modify my opencart and build Modules : 1. Seller area : · can manage own product only · for each seller Dashboard and Statistics · the seller can modify own order only · any products buy it by customers notify the seller who own this product by email and sms . 2. admin area : · admin can view and modify all order of sellers · admin can split Category for each seller (private Category other seller can’t look or modify inside it ) · admin can add or modify sellers and modify the information of the sellers ( phone , address ..etc ) only on admin area 3. sms Modules (in admin area only ): · box for user and password for the api ( I will Bering the api when the job start ) · admin can send sms for specific customer group or written number . · option : - click button for enable and disable : when customers make the order and auto notify him by sms with order summery . - click button enable and disable : when customers make the order auto notify the seller who sell the product with order summery and customer name . · button that when click on it give you a result with how many credit you have . Note : We don't need change in store front