Across a few industries the selection of items that a customer is valid, eligible or able to purchase can be in imposed. This could be based around specific accreditations the business must hold, security clearance, standard of a product (customer will only accept grade A for example). The current lookup logic to the item table from a sales document is not capable of handling a more advanced filtering logic. The work around of this "Item References" will require too much up keep or support from automation.

Rough idea on how this could work is below. I am sure there are many other ways to considered:

• This could be a valid use case of item attributes where a customer record holds a collection of values, which are present on items, that become the customers filter set for the item table.
• The standard lookup logic on the sales line could be a setup value. In this scenario it would be turned off to make use of a more advanced lookup/filtering
• If adding a line via the UX item numbers can still be manually typed and they will go through a more advanced validation. If a user wants to perform the action with button clicks, and the earlier mentioned setup is in place, the user may only do this by the "Select Items" feature. Given this opens a page, it will allow time for the additional filtering logic to be put in place
• Include an approval workflow for altering of a customers "Approved Item List"

If a design can be agreed for customers it could be used across on vendors too. For some businesses the fact you can add a vendor to an item (other places too) and then select any item for purchase is sometimes viewed as strange. This again could be driven by setup, so that the standard behaviour remains for the many that want to use it.