On Auxilio the Windows 10 VMs come with 120 GB internal storage. If you need to increase the storage, after requesting this by ticket you can add the storage as another drive or make one larger C partition.
To create another partition please use the Windows Disk Management Utility.
To extend the C partition you can use the free utility AOMEI as specified in this guide, section 3, Increase C drive space in Windows 10 with non-adjacent unallocated space