"It should not to be configured with a PC, but plug&play. When ariving in an other hotel it should just work when power is on."
No range extender will do that, because each hotel WiFi network has a different name, and you have to configure the extender (using its configuration interface on your laptop/netbook) to connect to that specific network router. You'll need to enter the password provided by the hotel in each case before the extender can make the connection. Your computer then makes its connection to the extender, and not directly to the hotel's router.