Thanks for the question. Many shopping cart softwares are not really designed for that purpose. For example, CubeCart has no way to do auctions, but there is software out there which can do what you wish. We currently promote PrestaShop and they have an Auction plugin that you can add, but it is not free. You can find many alternatives by simply going to your favorite search engine and searching for "online auction software". You will need to investigate the ones that best meets your needs.