For those trailering into Canada, don't forget about "purple gas". It is fine for any gas powered engine that is not used on roads. It does not have the road tax component in it. Do not use it in your truck. Huge fines!
It is selling for about 97 cents a litre / us$3.67 a gallon on South Vancouver Island.
For those of you trailering via Swartz Bay or via the Coho and heading up Island, purple gas is available at the outside northeast pump at the Mill Bay Shell gas station, about 35 mins north of Victoria.
There is a Costco gas station in Langford, about 3 mins off the highway, on the north side. Turn left before the Home Depot. No purple gas, but easily the cheapest gas in the Victoria area.
Have fun.