Tushar, thank you for posting this article! Very timely for me.
A couple of questions if you don't mind:
1) how do you use the Credential to authenticate to the a) Azure Subscription, and b) the SQL Database?
2) to access my resources I have to use the "RM" version of the commands such as Login-AzureRMAccount, etc. I guess this is because I added my objects to a Resource Group. You use command Get-AzureSqlDatabaseUsages but there is no equivalent that I can see for the "RM" version. Any thoughts?