Auction Drop-shop Management System

I need a system that will allow me to do the following tasks: 1) Register a consigner and the commission rate we will charge them 2) Check in an item for a consigner 3) Write a description, title, shipping cost, etc. for an item 4) Upload the item as an auction on eBay, Yahoo Auctions, iOffer, or Bidville 5) Track the item's bid status until the end of auction 6) When listing has ended, track payment from a buyer (PayPal or Google Payments) 7) When item has been paid for by buyer, print packing slip 8) Ship item via either USPS, FedEx, or UPS and email tracking # to buyer 9) Leave feedback for customer once they leave feedback for me I would like this to be a PHP/MySQL system. This should be a modular system so that if a new auction site needs to be added, it can easily be done.