As I mainly sell at auction, I don't require immediate payment.....I let the buyers bid over a 2 week period, sometimes they pay for the 1st item and I 'hold' until they've finished.....sometimes they don't pay until the end (depends whether they are repeat buyers or not).

If they also want 'BINs' added to the parcel, they do this at the end, by placing in cart.....confirming purchase, then I send them a combined invoice