Sure... get an older 8662 set and set it to Auto mode.
Otherwise this is dependent more on your router/firewall than the phone, essentially the phone needs to be able to go out and loop back in through the firewall, many routers do not allow this to occur, some do with no issues. The 53xx phones do not allow easy moving from local to remote and back. Could always buy a simple 5320 or 5330 set and setup Hot Desking, then anyone could take it and just log in with their extension.