Dont worry im happy to help,
Yes of course in my experience with Microsoft Sentinel because of the data ingress and Workspace Analitys you will be charge for it
I'm going to share some useful like so you can take a look at it
Azure Price Calculator for Sentinel so you can make a estimate
1- https://azure.microsoft.com/en-us/pricing/calculator/?service=azure-sentinel
Pricing cost tiers of Sentinel
2- https://learn.microsoft.com/en-us/azure/sentinel/billing?tabs=simplified%2Ccommitment-tiers
Play with the Azure calculator so you can have a estimate.
I hope this helps. Let me know if you have any further questions or need additional assistance.
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