[scoot]

Do you have any idea for how to ensure that the person has the funds when we need to charge the card?

You preauthorise the card for the amount at purchase, then complete the transaction on shipment.

[toomuchtodo]

Would you not preauthorize the card again right before shipment? What if their card is no longer valid, closed, or is past their credit limit?

[Shizka]

But that would still leave you with a risk that the card is closed or that the payment will get rejected, right?