The details for the items to be purchased.
unit_amountobject<money>Requiredcurrency_codestring<currency_code>RequiredvaluestringRequiredtaxobject<money>Optionalcurrency_codestring<currency_code>RequiredvaluestringRequiredupcobject<universal_product_code>Optionalbilling_planobject<order_billing_plan>Optionalbilling_cyclesobject<billing_cycle>[]Requiredpricing_schemeobject<pricing_scheme>Optionalpriceobject<money>Optionalcurrency_codestring<currency_code>RequiredvaluestringRequiredreload_threshold_amountobject<money>Optionalcurrency_codestring<currency_code>RequiredvaluestringRequiredtotal_cyclesintegerOptional1 and 999 for total_cycles). Regular billing cycles can be executed infinite times (value of 0 for total_cycles) or a finite number of times (value between 1 and 999 for total_cycles).start_datestring<date_no_time>Optionalsetup_feeobject<money>Optionalcurrency_codestring<currency_code>RequiredvaluestringRequired