SharePoint Online comes with a reasonable amount of free storage, but it’s surprising how quickly that storage can be consumed, especially if you use Office 365 retention policies. With that thought in mind, it’s a good idea to check what sites are consuming your SharePoint storage. This post covers how to write a PowerShell script to report SharePoint Online site storage, complete with a couple of bells and whistles.
https://office365itpros.com/2020/03/24/reporting-sharepoint-online-site-storage/
