How to check the usage of storage capacity for Premium Custom Content?
You can check how much free space is left in two ways.
When you are adding the custom content. Go to Admin → Content → Add Custom Content → Upload Content. The information is at the bottom of the page in the middle

When you are managing the custom content.
Go to Admin → Content → Manage existing custom content. The information is on the top right


NOTE: There is a hard limit on the GB storage so there will be no unexpected bills. If/when needed, the Admin can chat with his AM to purchase additional storage.