How can I have one invoice with multiple customers and products?

Hi there, Jay. Let me share with you some information about recording invoices in QuickBooks Online (QBO).

When recording an invoice in QBO, you'll be able to select multiple products and services from the Product/Service column. However, you can only pick a single customer name from the Customer drop-down. 

If you wish to send a single invoice that sums up the multiple products owned by different customers, you can create a dummy or new customer, then enter an invoice with all the needed products.

1. Sign in to QuickBooks.
2. Go to the +New icon, then tap on Invoice under Customers.
3. Fill in the information, then enter all the products you need.
4. Add the amount.
5. Save the transaction.

When you're ready to track the invoice payment, use this link as your reference: Record invoice payments in QuickBooks Online.

Just in case you don't need to keep the invoice, you can delete the transaction from your record after sending it.

If you have any other questions about your invoices or other customer entries, let me know by adding a comment below. I'm always here to help. Have a good one!

thank you for the reply @Angelyn_T 

Using this method:

"send a single invoice that sums up the multiple products owned by different customers,"

How can I associate the product to the owners?

I appreciate you for getting back, JayBlake. I can guide you on how to link the products to the designated customers.

As you create a single invoice that sums up the multiple products owned by different customers, you can use the Description column to add the customer names where the products belong. 

1. Fill in the information from the Invoice page.
2. Add the products under the Product/Service column.
3. Enter the customer names under Description.

I'm adding this screenshot as your visual reference.

Just in case you need additional customization with your invoice transactions, you this link as your guide: Customize invoices, estimates, and sales receipts in QuickBooks Online.

Please feel free to leave a comment below if you have any other follow-up questions about your invoices. I'm always here to help. Keep safe!

Why can't we add custom fields to products?

That would solve a lot of issue.