@Graham @ Work The only way to execute Windows 10 environments on Azure is using Windows Virtual Desktop with any of the required licenses mentioned here.
Instead of one VM and multiple snapshots I would suggest to have multiple VMs already configured and you can start/stop the one desired.
You can buy a Microsoft 365 Business Premium here and it would be enabled to use it on Azure through WVD.
You only needs one license because the software is licensed per user. It is compatible with Windows 10 Professional so your laptop can be used without any problem, but it would not be covered through this licensing.
Hope it helps!!!
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