Stepping in as a third QSP here in case Blake and Matthew are off line now.
We all agree. Control what users see by the reports that they use and their Role permission will control what they can see and edit.
When GM makes a car, it's the same car moving down the assembly line, not a duplicate of the car being created to drop in the next assembly stage.
You have a lot of tools to work with including form rules and role permissions.
You would be better off to rephrase your question if you are stuck in terms of controlling access to the same records by users in different Roles.
For example, a Custom Role permissions for a Role that says only allowed to edit if the Status of the record is X. You can also have any complex logic you like by making a dedicated formula field for this purpose called like [Low level Role allowed to edit?] and then the Custom Role permission is when that is checked, then users in that Role may edit.
Note that users in different Roles can be set up to have different dashboards and different tabe Home pages.
