We have a "quite finished" oscommerce based ([url removed, login to view]) website. Much code was modified to suit our needs and new classes were added to handle invoices and payments. I have a detailed report only on the first tasks that I have written some days ago for a developerin which I explain what has been already done and what has to be done. I have uploaded this PDF.
! ATTENTION !
I'm really happy for your "massive" replies but, please, provide me some portfolio's links where you have effectively changed some PHP CODE to osCommerce and not only personalization in graphics or templates !!! This will be VERY MUCH appreciated.