Automated PayPal Sale to QuickBooks Online Sales Receipt (n8n)

1. **Setup PayPal Webhook**: Start with a 'Webhook' node in n8n. Set the HTTP Method to POST. In your PayPal Developer Dashboard, point the Webhook URL to your n8n production URL and select the `PAYMENT.SALE.COMPLETED` event. 2. **Create QuickBooks Credentials**: Add a QuickBooks Online node. Authenticate using OAuth2. Ensure you have the 'Accounting' scope selected in your Intuit developer portal. 3. **Search for Customer**: Use the QuickBooks node with the 'Resource: Customer' and 'Operation: Get All' action. Use a filter expression: `{{ $json.payer.payer_info.email }}` to see if the user already exists. 4. **Logic Branch (IF Node)**: Add an 'IF' node to check if the search result from Step 3 returned an ID. 5. **Create/Update Customer**: If the IF node is 'false', use a QuickBooks node to 'Create' a customer using the PayPal name and email data. 6. **Set Variables (Set Node)**: Use a 'Set' node to map PayPal's `amount.total` (Gross) and `transaction_fee.value` (Fee). Use n8n expressions to ensure they are formatted as numbers: `{{ parseFloat($json.amount.total) }}`. 7. **Map Product/Service**: Use a 'Set' node or a 'Switch' node to map the PayPal `item_name` to your specific QuickBooks 'Product/Service ID'. If not found, set a default 'General Sale' ID. 8. **Calculate Line Items**: In the QuickBooks 'Create Sales Receipt' node, add two line items: - Line 1: Income (Gross Amount). - Line 2: PayPal Fee (as a negative amount) mapped to your 'Bank Fees' expense account. 9. **Configure Deposit Account**: In the Sales Receipt node settings, set the 'Deposit To' field to your 'PayPal Bank' asset account in QuickBooks. 10. **Error Handling**: Create a separate 'Error Trigger' workflow. Use a 'Sticky Note' to link the two, ensuring any failed API calls (like 401 Unauthorized or 400 Bad Request) alert you via Slack or email.

| PayPal Field | QuickBooks Field | n8n Expression / Transformation | | :--- | :--- | :--- | | `payer.email` | `Customer Email` | `{{ $json["payer"]["payer_info"]["email"] }}` (Required) | | `amount.total` | `Line 1: Amount` | `{{ parseFloat($json["amount"]["total"]) }}` | | `transaction_fee.value` | `Line 2: Amount` | `{{ -Math.abs(parseFloat($json["transaction_fee"]["value"])) }}` (Negative value) | | `id` | `Private Note` | `PayPal Transaction ID: {{ $json["id"] }}` | | `parent_payment` | `DocNumber` | Mapping the unique reference for audit trails | | `amount.currency` | `CurrencyRef` | `{{ $json["amount"]["currency"] }}` |

- **Webhooks vs. Polling**: Always use the Webhook node for PayPal to avoid hitting n8n execution limits through unnecessary polling. - **Sandbox vs. Production**: Ensure your n8n Webhook URL is the 'Production' one before going live, as the 'Test' URL changes every time you restart the workflow in the UI. - **Strict Rounding**: QuickBooks requires exactly 2 decimal places. Use `.toFixed(2)` in your n8n expressions to avoid 'Validation Error: Amount is invalid'. - **Rate Limiting**: QuickBooks Online API has a limit of 500 requests per minute. If processing bulk historical data, use the 'Split in Batches' node (batch size 50) with a 'Wait' node of 2 seconds. - **Tax Handling**: If PayPal doesn't break out tax clearly, QuickBooks may auto-calculate it based on the customer address, causing a balance mismatch. Use the 'GlobalTaxCalculation' field in the node to override this.

- [ ] **Webhook Handshake**: Send a Mock Webhook from PayPal Developer Tools and check the n8n 'Execution' tab for data arrival. - [ ] **Customer Deduplication**: Run the workflow twice with the same email to ensure a second customer record is not created. - [ ] **Net Zero Check**: Verify in QuickBooks that (Gross + negative Fee) equals the exact Net amount deposited into your PayPal Bank account. - [ ] **Account Mapping**: Confirm the 'Bank Fees' expense account in QuickBooks reflects the negative line item correctly. - [ ] **Audit Trail**: Ensure the PayPal Transaction ID is visible in the QuickBooks 'Display Name' or 'Memo' field for easy searching.