How do I get my progress invoice to show the previous balance and show the customer their previous payments on the prior invoices and total left ?

Hi there, @chris124.

I've got the steps to help you display the invoice details you need.

Let's check your progress invoice template and make sure the Account Summary section was selected in the Show on invoice box under the Content tab. This way, you can view the prior balance and payments made by your customer

Please see screenshot for your reference:

You can also review the customization of your sales forms. This way, you get to decide what information your customers see and only add the information that matters most to your business.

To record a partial payment to your open invoice check out this article for the detailed steps: Record invoice payments in QuickBooks Online. On the same link, you'll find steps on how to record multiple payments in QuickBooks Online as well as finding customers' balances.

If there's anything else that I can help you with aside from working with your invoice, please let me know by leaving a comment below. I'll be here to lend a helping hand. Take care always!