Hi @brrdg-21,
I appreciate you for joining the thread.
The steps provided by my peer @Catherine_B above are for an invoice template. As she stated, the Estimate summary field appears if you create an invoice from an estimate. With that said, you can see this option if you edit your invoice template, such as the Standard template. It's unavailable in your estimate templates.
On how you can add an estimate as an attachment to your invoice, follow these steps:
- Highlight the Sales tab.
- Select the Customers tab.
- Click on the customer in question.
- Tap the Filter tab, then choose Open estimates.
- Click the estimate to open the transaction.
- Hit Print or Preview, then Print or Preview again.
- Press Download.
This will save a PDF copy of the estimate to your computer. You can proceed to open the invoice you want to send your customer and attach a PDF copy of the estimate.
Check out this article for additional information: Email and customize sales form. Scroll down to the Customize sales form section for a detailed guide on how you can change how sales forms look and feel when your customers receive them.
Direct any other questions you have about sales forms in QuickBooks Online in the comments below. I'll be sure to handle it for you.