What is the monthly plan limit before I would see a charge for exceeding the limit and the cost per unit?

The plan limits currently apply to storage and transfer separately. So for our Standard Plan, in a month you can have a total of 50GB of storage use, and 50GB of data transfer for the flat fee. Anything above that during a calendar month would be billed at the per-GB price listed on our pricing page. In an example, if you had 50GB of total storage and your data transfer use was 60GB you would be billed your flat rate + (Overage Cost x 10GB) for the additional data transfer above the base plan.

Note: Data transfer Usage is comprised of Download and Preview actions.