Build an Online Store with EBAY API

I have several Websites that are using EBAY RSS Affiliate Feed, getting reasonable revenue for my niches using EBAY Partner network commission. Need EBAY API code (Online Affiliate Store) installed on my site, I should be able to change the Categories/niches based on my site requirements.. I am looking for Developer that can complete this simple project. Payment will be after the working software is delivered. Expecting a professional that has delivered EBAY Affiliate code.