JUMP TOMerchant APIRefundsList all refundsgetRetrieve a refundgetPaymentsList all paymentsgetCreate a paymentpostRetrieve a paymentgetCancel a paymentpostComplete a paymentpostRefund a paymentpostList all payment refundsgetMulti-Card PaymentsComplete a multi-card paymentpostList all multi-card paymentsgetCreate a multi-card paymentpostRetrieve a multi-card paymentgetUpdate a multi-card paymentpatchRefund a multi-card paymentpostList all multi-card refundsgetCancel a multi-card paymentpostMerchant WebhooksAdd a webhook endpointpostList all webhook endpointsgetUpdate a webhook endpointpatchRemove a webhook endpointdeleteRetrieve a webhook endpointgetItemsRetrieve an itemgetUpdate an itemputCreate an itempostList all itemsgetGroup PaymentsComplete a group paymentpostList all group paymentsgetCreate a group paymentpostRetrieve a group paymentgetUpdate a group paymentpatchCalculate group sharepostRefund a group paymentpostList all group payment refundsgetExchange RateGet latest exchange ratesgetGet historical exchange ratesgetEventsRetrieve data for an eventgetFind all eventsgetCustomersRetrieve a customergetUpdate a CustomerpatchDelete a CustomerdeleteList customersgetCreate a CustomerpostCheckoutsRetrieve a checkout sessiongetUpdate a checkout sessionputCreate a checkout sessionpostList all checkout sessionsgetCancel a checkout sessionpostUpdate an itemput https://sandbox.handsin.com/v1/items/{itemId}Update an item by supplying the correct parameters.