Upload & Sell: Off
I'm a bit late to this, but I had the same problem - Zenfolio will not accept payment for self-fulfilled orders. They will send an email to the buyer with the total and list of products ordered with a blurb that says "Please arrange for payment through <insert seller name here>". It's true you can go through paypal, but it's horribly inconvenient and confusing for someone who just wants to order some prints. Angeposs - how were you able to accept cards through zenfolio? I would love to know this because I'm about to leave zenfolio over this.
I'm setting up a photodeck site now, which has a much better and fully integrated e-commerce solution built in. They take 0% comission, but all products must be self-fulfilled (there is no direct fulfillment through 3rd party labs). I like this though, because I can order the prints I CAN'T do at home from Adorama Pix at half the cost of the direct fulfillment options through zenfolio. less cost = more profit and more savings for the client