Limit account from creating numbers, carriers etc

[sammachin]

When setting up a new account I would like to be able to limit what that account can create in terms of phone numbers & carriers. And possibly speech providers too.

The scenario is that I have a single carrier with all numbers being delivered to the platform but as an admin I want to be able to assign a number to an account rather than letting users grab them.
I can create the number as the admin and then link it to that account but this doesn't prevent the account users from adding their own too.