PUT api/ShoppingCartItems

{
  "Quantity": 1,
  "Price": 2.0,
  "InstallmentPrice": 3.0,
  "WebProductId": "sample string 4",
  "InvoiceId": "sample string 5",
  "AccountId": "sample string 6",
  "EventPricingId": "sample string 7",
  "SelectedMealOption": "sample string 8",
  "PortalId": "sample string 9",
  "AttendeeId": "sample string 10",
  "ApplicationId": "sample string 11",
  "GuestFirstName": "sample string 12",
  "GuestLastName": "sample string 13",
  "RequiredParentEventWebProductId": "sample string 14",
  "ChargeTaxes": true,
  "ChargeShipping": true,
  "AccountingCompanyId": "sample string 17",
  "DonationFrequency": "sample string 18",
  "RecurringBilling": true,
  "WebProductAnswers": [
    {
      "Question": "sample string 1",
      "Answer": "sample string 2",
      "QuestionId": "277ac43d-5c0b-4726-8acb-4d4dfff8cd7c"
    },
    {
      "Question": "sample string 1",
      "Answer": "sample string 2",
      "QuestionId": "277ac43d-5c0b-4726-8acb-4d4dfff8cd7c"
    }
  ],
  "IsWaitlisted": true,
  "Attendee1Id": "sample string 21",
  "CartGroupId": "sample string 22",
  "BrandedApplicationId": "a3eb698c-0338-4461-b0f4-4ee72465e5f1"
}

<NewShoppingCartItem xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/AltaiStandard.Core.Models">
  <AccountId>sample string 6</AccountId>
  <AccountingCompanyId>sample string 17</AccountingCompanyId>
  <ApplicationId>sample string 11</ApplicationId>
  <Attendee1Id>sample string 21</Attendee1Id>
  <AttendeeId>sample string 10</AttendeeId>
  <BrandedApplicationId>a3eb698c-0338-4461-b0f4-4ee72465e5f1</BrandedApplicationId>
  <CartGroupId>sample string 22</CartGroupId>
  <ChargeShipping>true</ChargeShipping>
  <ChargeTaxes>true</ChargeTaxes>
  <DonationFrequency>sample string 18</DonationFrequency>
  <EventPricingId>sample string 7</EventPricingId>
  <GuestFirstName>sample string 12</GuestFirstName>
  <GuestLastName>sample string 13</GuestLastName>
  <InstallmentPrice>3</InstallmentPrice>
  <InvoiceId>sample string 5</InvoiceId>
  <IsWaitlisted>true</IsWaitlisted>
  <PortalId>sample string 9</PortalId>
  <Price>2</Price>
  <Quantity>1</Quantity>
  <RecurringBilling>true</RecurringBilling>
  <RequiredParentEventWebProductId>sample string 14</RequiredParentEventWebProductId>
  <SelectedMealOption>sample string 8</SelectedMealOption>
  <WebProductAnswers>
    <WebProductAnswer>
      <Answer>sample string 2</Answer>
      <Question>sample string 1</Question>
      <QuestionId>277ac43d-5c0b-4726-8acb-4d4dfff8cd7c</QuestionId>
    </WebProductAnswer>
    <WebProductAnswer>
      <Answer>sample string 2</Answer>
      <Question>sample string 1</Question>
      <QuestionId>277ac43d-5c0b-4726-8acb-4d4dfff8cd7c</QuestionId>
    </WebProductAnswer>
  </WebProductAnswers>
  <WebProductId>sample string 4</WebProductId>
</NewShoppingCartItem>

Sample not available.