your going to need more than one mileage run for 18k... but just to get you to join the team heres some more help. PS UA or CO are more miles and the same price. this is less time off work and less hotels and you get 50% bonus points with AC and hopefully you have SSWU or why are you doing it?

Montreal (YUL) to Tokyo (NRT) - Wed, Dec 2
Montreal (YUL) to Toronto (YYZ) - Wed, Dec 2
Air Canada 431 Dep: 10:30PM Arr: 11:50PM 1h 20m Airbus A320 Coach (W)
Layover in YYZ 12h 10m

Toronto (YYZ) to Tokyo (NRT) - Thu, Dec 3
Air Canada 1 Dep: 12:00PM Arr: 3:05PM 13h 5m Boeing 777 Coach (W)
Fri, Dec 4


Tokyo (NRT) to Montreal (YUL) - Sun, Dec 6
Tokyo (NRT) to Vancouver (YVR) - Sun, Dec 6
Air Canada 4 Dep: 7:00PM Arr: 10:50AM 8h 50m Boeing 767 Coach (S)
Layover in YVR 3h 50m

Vancouver (YVR) to Montreal (YUL) - Sun, Dec 6
Air Canada 112 Dep: 2:40PM Arr: 10:23PM 4h 43m Airbus A320 Coach (S)


Cost per passenger (including taxes & fees) CA$1,166.98
Total cost for 1 passenger CA$1,166.98