I’m trying to achieve this using user permissions instead of Sharing/assigning the document.
If I wish to share the document with only 1 subcontractor, I can create a linked field and select the subcontractor in this field. Then via user permissions, I can make that linked subcontractor available to the subcontractor.
However, if I want to share the document with all 3 subcontractors, setting user permissions doesn’t seem to work so well. I can create a child table and set the linked field in the child table. But this does not restrict the other unassigned subcontractors from being able to view the list of all the documents. Although it does restrict them from being able to open the document. But in this case, the other subcontractors are aware that the document was shared with a particular contractor (not ideal).
Any way around this?