My app is Sallle Channel, 100% (in SC section of Shopify Admin and Sales Channel option enabled in Partner Dashboard).
Here is full response for creation an checkout:
{
"checkout": {
"clone_url": "https://test.myshopify.com/6778552435/checkouts/3fc67385517734dedf956272a8179995/clone",
"completed_at": null,
"created_at": "2019-03-27T03:03:17-04:00",
"currency": "GBP",
"presentment_currency": "GBP",
"customer_id": null,
"customer_locale": "en",
"device_id": null,
"discount_code": null,
"email": null,
"legal_notice_url": null,
"location_id": null,
"name": "#5700494360691",
"note": "",
"note_attributes": {},
"order_id": null,
"order_status_url": null,
"order": null,
"payment_due": "0.00",
"payment_url": "https://elb.deposit.shopifycs.com/sessions",
"payments": [],
"phone": null,
"shopify_payments_account_id": null,
"privacy_policy_url": null,
"refund_policy_url": null,
"requires_shipping": false,
"reservation_time_left": 0,
"reservation_time": null,
"source_identifier": null,
"source_name": "2448289",
"source_url": null,
"subtotal_price": "0.00",
"shipping_policy_url": null,
"tax_exempt": false,
"taxes_included": true,
"terms_of_sale_url": null,
"terms_of_service_url": null,
"token": "3fc67385517734dedf956272a8179995",
"total_price": "0.00",
"total_tax": "0.00",
"total_tip_received": "0.00",
"total_line_items_price": "0.00",
"updated_at": "2019-03-27T03:03:17-04:00",
"user_id": null,
"web_url": "https://test.myshopify.com/6778552435/checkouts/3fc67385517734dedf956272a8179995",
"line_items": [],
"gift_cards": [],
"tax_lines": [],
"tax_manipulations": [],
"shipping_line": null,
"shipping_rate": null,
"shipping_address": null,
"credit_card": null,
"billing_address": null,
"applied_discount": null
}
}
So, as you can see total Price is 0, but product price is £529.00.
variant_id for Checkout request is taken from /cart.js output