Milli, the last time we went to Mexico I think we took Canadian, US and Mexican. We stayed at the Palladium and we could change our money at the resort. If memory serves me right, would could only us Mexican currency while on the resort. While off the resort we could use US or Mexican. This time I am bringing Mexican and US for sure. I was thinking about the Cdn $ question myself while I was walking to work this morning.
I know the Cozumel gang will be able to answer it.
If you are flying through Toronto, I think there is a money change place in the terminal that you may be able to convert some money so that you have a few pecos in your pocket when you arrive.
One other thing, are you aware that Coba is not directly on the beach? It is the newer addition to Bahia, but not beachfront. Don't know if that is a consideration for you or not.
4 more sleeps for me.