E-commerce Upoader - Magento? amazon, ebay, mercado libre, sears, new egg, bonanza, buy

We are currently uploading to the following places: Amazon,amazon store, Ebay, Mercado Libre, sears, new egg, bonanza, buy (rakuten). We need someone to build us a custom marketplace up-loader with the following options, use magento, or any other way [login to view URL] want to upload to these places automatically based off of a csv file. [login to view URL] want to be able to manage all aspects of our inventory from within the system [login to view URL] would like to be able to configure and upload to other networks in the future. [login to view URL] able to auto pull a new file from a location We are open to anything... Magento or any other software. You will have to give us exact directions on how to use it. IN YOUR MESSAGE- Explain to me how this will work, what platform or program you will use, and explain the pros and cons