Add paypal subscriptions to user panel and work with ebay and amazon API

Hi, I have an existing login system which works fine. I need to make it so a user can subscribe with paypal, and then enter their ebay API details. Then every hour the site needs to grab the users ebay items, add a percentage markup onto the price (getting the price from the ASIN on Amazon) and then re-upload that price to ebay. It is basically a way of the user having their ebay items dynamically updated based on the price of the product on Amazon + A markup percentage. This is the full job list: [login to view URL] Any questions please feel free to ask.