I will let you all in on a little secret about flying to the US via Vancouver, Canada. If you fly Air Canada or United, when you land in Vancouver, there is a special direct route from your arrival gate to US customs. If you fly any other airline, you have to clear Canadian customs, and then go check-in through US departures. There is a special Air Canada/United baggage claim after you go through your special customs gate if your luggage has been checked through to a US destination. No Canadian transit visa required. In addition, my experience is that US customs in Vancouver is much quicker and the agents politer than say LAX or SFO. I was seriously thinking about an Air Canada flight home too, but we could not figure out how to get that stupid transit visa. I had emailed the Canadian embassy in Guangzhou, and they said they don't do the transit visa there. Then I tried the one in Hong Kong, and they never responded. We gave up on the idea, because I had no idea how to get this transit visa..