VPN for different companies using one VPN Router?

I´m a bit fresh to VPN so bear with me.

I´m setting up five different servers in a server room for a customer and all those five servers are owned by different companies. I want to give them all the possibility to access their machines with VPN and thought i get a VPN router for it.

They all have static public IP:s, can i have one VPN router handle all five servers (as long as it handles five VPN tunnels) or do i have to get one for each machine?

Can i limit access so that they just see their own server and never sees the other servers on the network?

Any input on how to solve it is appriciated!

/ Christian