Depends what you want to do with it, are you running a shop? Otherwise a cheap one, the Autel AP200 that does all the codes is just $61.08 at Amazon. Walmart used to have it for $50 but I don't see it listed there anymore, maybe it's out of stock.
I'd rather support other online retailers besides Amazon, but where in Canada can Autel's be purchased?The Autel MD806 Pro is great high end DIY scanner that gives you a lot of added features like SRS relearn, ABS codes, DPF, etc that cheaper scanners won't have. It can't do some things that professional shop grade scanners can do like bi-directional control, ECU programming, etc so if you are running a shop it would be somewhat lacking as a primary scan tool.