I just reviewed that and am under the impression that I would have to create a new Seller Details profile for every item that has a varying shipping amount. I wish there was a way to edit the entire HTML for the item description portion without loading seller details by hand. OK, I just realized I can provide my own custom template and fill in all the info in the item description that would normally appear in the Seller Details Profile. Albeit, not the optimal way, but the template won't be too hard to change around.