I'm no expert, but each user can create an xpra session, which they can connect to remotely by ssh. You just need to install it and provide ssh access. I don't

I'm no expert, but each user can create an xpra session, which they can connect to remotely by ssh. You just need to install it and provide ssh access. I don't know whether other options might work. x2go might be an alternative, where you connect to get a complete desktop.