Another option is a train/bus combo. The Amtrak train leaves SEA at 5:30 p.m. and arrives in Bellingham at 8:00 p.m. and the Amtrak bus partner leaves 5 minutes later for a 9:30 p.m. arrival in YVR. The one-way coach fare is $22, and a biz class upgrade would be not a whole lot more. We are contemplating getting there this way too but are still undecided at this point.