What level of permission is needed to set an item for archiving? Is it only Admins and through a workflow?

If we are talking about the mark for archiving option here, that requires "full control of vault" administrative rights: Administrative rights for marking objects to be archived and for clearing the archiving marker

You could also use some custom property for this, e.g. a Boolean property "Ready for archiving" that regular users could add to the document metadata. You could then use "Ready for archiving = Yes" as a filter when archiving content (e.g. one-time export or scheduled replication to an archiving vault, depending on your archiving process). Or if the documents are in a workflow, you could add a separate "Ready for archiving" state where the document could be moved.

Thanks Joonas, that will work. Cheers

Thanks Joonas, that will work. Cheers