How to Access remote VM over/ With VPN
The way we usually set this up is to enable RDP access to the VM. But instead of opening the port 3389 in the router we setup a VPN server inside the network of the VM instead. This can be done on the same router if the router has VPN support.
To connect, Make a VPN connection to the network first, then start Microsoft Remote Desktop and connect to the local ip of the VM over port 3389.