Online Sale & Purchase

Hi, I am running my e-commerce solution (my online store) which is having all the functionalities i want. now i am also selling my products on e-bay. i have my own store i have created on ebay. My Problem is i have to add the item in both the places, and i have a big inventory, so i am looking for kind of solution where i can add items on my web store (my own website) and it'll also add the item on my ebay store too. I also require a solution like all sales i made in my ebay store will reflect on my own ecommerce store with all information of buyer where i have to ship the item. also able to give feedback for the same from my front store. so ultimately i want all the basic functionality like adding item / in buy now option / auction / all sales related activities etc. from my front store. if you are serious programmer / developer / consultant who have ready available solution then you can go ahead and bid the project. only serious bidders bid... please. Thanks