Storage included increases with the number of active users.
Business Plan: Included per user 5 GB storage, 5 hours streaming, 1 SMS.
Education/Government Plan: Included per user 200 MB storage, 5 hours streaming, 1 SMS.
If you upload more than is included in you subscription you will just be invoiced based on the list price for overages:
100 GB Extra Cloud Storage $10.00
1.000 Extra Streaming minutes $2.49
100 extra SMS $10.00 $