Good day, projectservicesb.
You can either add the terms and conditions in the Message on invoice box or download a file in the Attachments page.
Note: The character limit on the Message on invoice box is 4000. Here's an article for reference: QuickBooks Online file size and feature limits.
To add an attachments, please make sure you have the following file types:
- PDF
- JPEG
- PNG
- DOC
- XLSX
- CSV
- TIFF
- GIF
- XML
Then, follow these steps to upload the file:
- Click the Gear icon located in the upper right-hand corner.
- Under Lists, click Attachments.
- Click on the Drag/Drop files here or click the icon field.
- Select the terms and conditions file and click Open.
When you create an invoice, you can select the file by clicking the Show existing link under the Attachments box.
Here's a sample screenshot:
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This article also contains more details about attachments.
Let us know if you need more help. Thanks.