Let me share some details about the old invoice templates in QuickBooks Online(QBO), renewcc.
Previewing how the invoice appears to your customers is unavailable within the invoice window. That's why a view-only prompt appears when selecting your previous invoice templates.
Otherwise, you can choose the Review and send or Print and download option to view how the invoice appears. If you want to set your old template as the default, you can select the Manage option and follow the prompts in the Custom forms styles page.
You may also want to visit this resource to see what is new with our estimates and invoices: New estimates and invoices in QBO.
When you're ready to receive your customer payments, you may refer to this article for guidance: Recording invoice payments QBO.
Update us by leaving a comment below if you have further concerns about managing your invoice templates. We're always ready to lend help again.