When planning an Exchange migration I like to review the storage quotas configured on the existing databases. This ensures that new databases are configured with at least the same quota level and not inadvertently left with a smaller quota level, and also presents an opportunity to review quotas in the organization in case they can be increased or removed entirely.
Here is a basic script that can be used to check all mailbox and public folder databases and report their storage quotas.
Download the script file here: StorageQuotas.ps1 (downloaded 450 times so far)
Simply run the script from the Exchange Management Shell.
[PS] C:\Scripts\Exchange2013Planning>.\StorageQuotas.ps1 Processing MB-HO-01 Processing MB-BR-01 Processing MB-HO-Archive Processing MB-BR-02 Processing MB-HO-04 Processing MB-HO-02 Mailbox database storage quota report saved as C:\Scripts\Exchange2013Planning\StorageQuotas-MailboxDB.csv Processing PF-BR-01 Processing PF-HO-01 Public folder database storage quota report saved as C:\Scripts\Exchange2013Planning\StorageQuotas-PublicFolderDB.csv
The two CSV files are written to the folder where the script is run from.