How to enter multiple lines onto a from at once with some portion of that form being autofilled?

[WheresTheBeef]

Hello All!!!

Here's my use case: I'm trying to build a simple purchasing tool to help facilitate our buying process. This tool will be able to show current inventory on hand, show current run rates, and allow users to input a simplified purchasing request so that we can consolidate our buying power. 

We built a simple form, but our initial pushback was that it was too cumbersome to enter in a request for each item separately. They are asking for the app to show a list of items and for them to be able to go down the list of items and enter in the amounts before submitting them all at once. 

For the life of me I can't figure out how to do this with AppSheet. Have any of you built a similar use case?