Configure remote access (OpenVPN?) to 4 desktops & partition home network

I need to enable secure point-to-point connections between 4 machines (2 Windows, 2 Ubuntu) on my home network and 2 developers I work with, without exposing other machines on my home network.

I'm thinking OpenVPN + some sort of subnet or network partition (I have a Peplink BalanceOne router and switch that can be configured as needed).