Currently, if I have a project collaborator (1099 subcontractor) with project related expenses, they can not record them (don't see the expense tab in the project view). The only way I can give them access is by converting them to a restricted use and give them access to the full accounting module with full visibility into financials. As a result, I have to collect the expenses and receipts and record them myself. This is a great place for more granular permissions for collaborators and / or restricted users.