Get a cart ready for checkout. Re-checks that everything is still available for the date and that the cart meets that date's minimum, then returns the items, the price breakdown (delivery, fees, tax, total, deposit due today), what the customer still has to enter, and handoff_url: a private link that opens this exact cart at checkout on any phone or computer. This tool never pays or places the order: the customer pays on that page, or, once they have authorized it, you complete checkout there for them. Give handoff_url to the customer only.