Within each client's Vault, you will find two subfolders available to you. The second of these is the Private Folder:
The Private folder is where you and your clients can upload private documents. Any documents uploaded here will only be seen by you. The client will also have a separate private folder where they can upload documents; you will not see those documents.
Important Note: File Size
While there is no limit on the total number of files you can load into the Vault, please note that individual files must be under 25 MB in size.
You can access your Private Folder for a client within the Vault tab of their individual client plan.
