By now you've probably heard that Fairfax Financial, the insurance giant headed by value-investing legend Prem Watsa, has entered into a deal to buy struggling Canadian smartphone maker BlackBerry (BB -0.69%).

Watsa has one of the most distinguished investing track records this side of Warren Buffett by shrewdly buying undervalued stocks on the down and out. As the CEO of BlackBerry's largest single shareholder -- and the chairman of BlackBerry's board until recently, stepping down to avoid potential conflicts with the buyout -- it's fair to say that Watsa knows BlackBerry better than just about anyone out there.

And while BlackBerry's struggles are undeniable, Watsa's deep expertise and investing acumen also can't be overlooked. In this video, Fool contributor Andrew Tonner looks at BlackBerry's potential valuations to see just how great a deal Watsa might be getting.