Add custom Reporting to Joomla Auction Site

I'm designing an auction site in Joomla using Auction Factory. ([login to view URL]) It's designed for multiple users to be uploading auctions, just like ebay. My client is going to be the only auctioneer though and want the ablity to receive financial reports from the site. So this project would entail customizing the plugin to generate said reports with fields such as total sales, etc, still to be determined. Not on a set basis but on request - so the admin would log in and hit the 'report' button and receive the report..probably through an excel file or something. Need this done within a week or so.