The cancellation fee for your particular contract depends on the financing you got for your device as well as where you’re at in your contract.
Let's take an example:
You’ve agreed to a 24 month contract with Fizz, and there’s 6 month left to it. You still have to pay 6 / 24 = 1/4 of the cost cell phone after any upfront payments you may have made.
So if your cell phone was worth 1000$ and that you paid 200$ upfront, the financing is 800$. The cancelation fees are 800$ / 4 = 200$. And nothing more!
And after you pay that, your device is supposed to be unlocked for free! You’re protected by the CRTC.