VROOM provides you a detailed overview of user accounts established in the selected database. You can check the status of accounts, and the default locations for user-created objects and temporary segments:
You can view lists of objects created in the user’s schema, (as well as structural details of schema objects, available elsewhere in VROOM):
And, you can examine roles, system and object privileges that have been granted to user accounts -- for each user, you can see which tables outside of their own schema they have permission to read, modify or delete: