I have been looking for a way to support G-Suite clients without them having to pay an extra license for me to admin their G-Suite Accounts
The question on whether this can be achived has been asked and answered in the Google forums with two answers:
The second answer is the one i’m interested in:
Install Cloud Identity Free. https://support.google.com/cloudidentity/answer/7295541?hl=en Then create a logon (Without License Allocated). Then Assign Super Admin. This is how you can manage multiple clients without incurring a cost.
So I’ve just tried it and it appears to work.
Pro-Tip: You might want to hide the new super admin account from being visible in the directory too.
Update – When can’t you immediately use a Cloud Identity as an non-billed Admin Account
Tried this with a G-Suite account provided through a reseller and you can’t add Cloud Identity without going through the reseller.
So before you could do this you would have to approach the reseller to enable cloud identity Free which they might not want to do because it would by-pass their revenue stream.