|I would suggest you need to do a bit more homework starting with defining what services you are trying to provide.|
Hamachi only allows one connection at a time. Since you mention staff I suspect this is not workable.
Having folks directly on the server means you need to have good gpo's/restrictions that protect the servers core files and systems.
In a professional environment like mine we do vpn clients to a vpn router that requires authentication which in turn we load the Citrix client that attaches to our Citrix servers which in turn allows access to our networked resources.
Our Citrix servers only have Office and various other client apps installed on them. We would never allow direct logon to the actual app servers since this can lead to their being compromised.
Clearly understand the security risks presented by various options.
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