Program to purchase products from eBay

I would like a program developed to purchase products from eBay. Some of the specifications would be as follows - 1. Field to specify product link 2. The script should navigate to the product and purchase mutliple variations of a product. Let's say there are 5 designs - A, B, C, D & E and 60 products within each design. It should go and purchase A1, A2, etc.