South african auction script

I want a site to mirror the functionality of [login to view URL] The look and design should be different but the functionality and features must be the same. the script must be able to work on a linux server. I need THE SCRIPT ONLY as the editing and design will be done by myself. I just dont know how and where to start with writing the script needed and searched through a few downloadable scripts but cant find what i am looking for. currently using phpauction script on my site so even if someone knows how or where to edit/add to make the site more user friendly in terms of a link to all new actions posted that updates every 15 minutes and list all new auction listed in the past 4 hours ranging from newest listings first to latest on the last page as well as a closing soon option that would funtion the same as the "whats new" option. as well as an option to add a link where "transactions not completed" can be filed in order for the buyer and seller to both give their side of the story as to reasons why it was not completed so that success fees can be refunded to the seller. also to edit the auction closed email that gets sent to the highest bidder as well as seller to have each other's full details in order to complete the transaction. Winner bidder will be paid in three equal monthly installments after the project is finished. No exceptions to this rule please.