Consolidate Google Workspace Data

I hold super-admin rights on a legacy Google Workspace tenant that used to serve 33 users. Only my own account is still active, yet I am not certain whether the former users’ Gmail and Drive data is still reachable.

What I need done
• Verify the status of every dormant mailbox and Drive so we know exactly what is still retrievable.
• Migrate all content—both Gmail messages and Drive files—from those 33 accounts into my single owner account. I would like the email routed directly into my mailbox (labels, original timestamps, and senders intact) and the Drive material moved or shared so I retain ownership without losing folder structure.
• Deprovision the redundant accounts cleanly, update licences, and leave me on a 1-user Business plan ? with the full 1 TB storage entitlement. NB I do not require a Business account for business activity but for access and archive - is there a more suitable account or subscription?
• Restore normal delivery for my domain email so new messages flow to my mailbox immediately after the consolidation.

Acceptance
Migration is complete when I can see every former user’s mail under a clearly named label tree, the Drive hierarchy is visible under my account with ownership transferred, and Google Admin shows only one licensed user. No data loss or permission errors are acceptable.

If you’re a certified Google Workspace administrator who has handled multi-user consolidations before, I’d like to hear how quickly you can schedule this one-off project and any toolset you prefer (e.g., Google Takeout, GAM, Admin SDK, or Workspace Migrate).