In addition to the below, you may need a copy of the ticket. If you are just doing a MR turn around the consulate may not grant you a visa. No Visa -, they will not allow u pon the flight. No tour scheduled, no hotel booked, no invitation letter. You may be out of luck. If u really want to go spend 2 days in the city and enjoy. Be usre to take the Mag Lev.