5 Tips for Cost Management in Azure
1) Azure Spot VMs
Virtual Machines are available at extremely low cost and can be utilized for various scenarios in dev/test/lab environments
2) Azure Advisor
provide best practice configuration/personalized actionable recommendations after complete analysis.
Azure Advisor is free to use
Deploy an entire range of Iass and Paas services using preconfigured artifacts
3) Azure DevTest Labs
4) Documentation
start with a high-level design document (HLD) and describe it with a low-level design LLD document with peer review. 
Stop your VMs through PowerShell/ Azure CLI or via console, this would take your VMs into a "Stopped (deallocated)” state. Now you would save and stop paying for VM's costs
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