using Gr4vy;
using Gr4vy.Models.Components;

var sdk = new Gr4vySDK(
    id: "mattilda",
    server: SDKConfig.Server.Sandbox,
    bearerAuthSource: Auth.WithToken(privateKey),
    merchantAccountId: "default"
);

var res = await sdk.Buyers.UpdateAsync(
    buyerId: "fe26475d-ec3e-4884-9553-f7356683f7f9",
    buyerUpdate: new BuyerUpdate() {}
);

// handle response

{
  "type": "buyer",
  "id": "fe26475d-ec3e-4884-9553-f7356683f7f9",
  "merchant_account_id": "default",
  "display_name": "John Doe",
  "external_identifier": "buyer-12345",
  "billing_details": {
    "first_name": "John",
    "last_name": "Doe",
    "email_address": "john@example.com",
    "phone_number": "+1234567890",
    "address": {
      "city": "San Jose",
      "country": "US",
      "postal_code": "94560",
      "state": "California",
      "state_code": "US-CA",
      "house_number_or_name": "10",
      "line1": "Stafford Appartments",
      "line2": "29th Street",
      "organization": "Gr4vy"
    },
    "tax_id": {
      "value": "12345678931",
      "kind": "us.ein"
    }
  },
  "account_number": "<string>",
  "created_at": "2013-07-16T19:23:00.000+00:00",
  "updated_at": "2013-07-16T19:23:00.000+00:00"
}