Thank you for your post!
When it comes to Microsoft Defender for Cloud pricing, I wasn't able to find any information on short-lived resources such as VMSS within the pricing page. To hopefully help point you in the right direction, from my understanding after reviewing the pricing page - VMSS should fall under a Compute resource (VM) and depending on your MS Defender for Servers Plan (1 or 2), you should be charged $0.007 (per Server per hour) or $0.02 (per Server per hour) respectively.
Note: Microsoft Defender CSPM protects across all your multi-cloud workloads, but billing only applies for Compute, Databases, and Storage resources. Billable workloads are VMs, Storage Accounts, OSS DBs, and SQL PaaS & Servers on Machines.
However, since this question is more pricing related, I'd recommend reaching out directly to the Sales team via the Chat feature on the pricing page to get a more detailed answer.
I hope this helps!
If you have any other questions, please let me know. Thank you for your time and patience throughout this issue.
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