There is a storage space allocated for the account based on the number of users. The storage can be increased if needed - send an email to contact@projectplace.com if your workspaces or your account run out of storage.
The performance of a workspace depends on how many items there are and not how big the items are. Many items will usually make the workspace slower.
To see used storage on account level:
This information is recalculated every morning at 5:30 CET.
To see used storage for each workspace:
Workspace administrators can also see the used storage for a workspace.