Auction facility on site

Auction Page Brief There is a page on my clients website which has an auction on it. Presently it is empty, but my client want to change it and put new products in it. It needs to work in the following way. My client will put items he wants to sell on this section via the Access database which supports the website. Each item in this section will have an Add To Cart button beside it. When an item is first put on this section it will start at a particular price and gradually lower in price automatically over a period of time. A shopper can then decide to purchase the item at any time or wait for it to go down in price. If the item is purchased it will disappear from the site as it had been bought. If the item Is not purchased it will continue to go down in price until eventually it gets to it’s lowest price and then it will disappear from the site after a certain period of time. My client would like it to work in the following way: The price of any product to go down between 2 and 7 increments The period of time between increments can be set in minutes, hours and days. The amount it goes down in each increment can be set in £’s Once item is purchased or the last increment of time has elapsed then the item should no longer appear in the website, but it should still be in the database. Maybe there should be a column with a check box to indicate on website and another column to indicate if it had been sold. The auction page should be able to display multiple items, have a Name, Description, add to cart button and the current price. All images should have click to enlarge feature.