This information is for package bundle users.
It's possible to select individual package child items for invoicing, without invoicing the parent item or other package items. This could be used if you wanted to, for example, invoice for hardware sent in advance of the rest of the package.
A package that has been part-invoiced can then be invoiced, which will pull any remaining items through to invoice.
Individual packages must be configured as part-invoiceable from settings.
To do this, from Settings - Product Bundles, you must check the Allow Part-Invoicing box against each eligible package bundle.
From a sales order record, you can check a child item to be invoiced.
Note that only the package parent item will show as Invoiceable in the grid view, but child items may be invoiceable individually as long as they are:
Not hidden from bill
Part of a part-invoiceable package
Invoicing the package parent will then invoice the remainder of the package.
Invoicing the package parent will always pull through all child items as long as they have not been invoiced already. Items that are hidden from bill can only be invoiced by invoicing the parent. The parent item itself cannot be selected for part-invoicing.