Existing buyer purchases with a new card

1. Show the buyer (customer) they're default card
2. Show the buyer all of their cards
3. Buyer elects to enter a new card, which would be tokenized
4. Verify that CVV and AVS checks pass
5. Make the new card the default card, which would also add it to the list of all the buyer's cards
6. Create a new order for the seller
7. Debit the buyer for the amount of the sale, and define the marketplace fee
8. Update the order with the shipping tracking information