Off the top of my head (seconds after I read the post), I can’t think of a way to build such a system natively within Airtable. It would require multiple iterations of:
- Pick a panel
- Set the quantity for that panel
…all in a form that wouldn’t care if you wanted to add one panel or several dozen. Airtable forms aren’t designed for that kind of flexibility. This would require integration with a third-party form tool like Jotform, Typeform, etc.