Hi David Kim , Thanks for posting your query on Microsoft Q&A.
Yes, you are correct. The Azure dedicated host cost covers only the CPUs, Memory, and OS Disk
Additional attached disk to the VM would be a separate cost from the dedicated host cost.
Users are charged per dedicated host, regardless how many VMs are deployed.
The host price is set based on VM family, type (hardware size), and region. A host price is relative to the largest VM size supported on the host.
Software licensing, storage and network usage are billed separately from the host and VMs.
If you have more pricing questions, you can also request a pricing quote for your specific scenario and get answers to your pricing questions. You can get one-on-one guidance on Azure pricing here by using Chat or Call options: https://azure.microsoft.com/en-us/pricing/contact/#contact-sales
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