News of the potential buyout comes just after the firm announced a massive restructuring on Friday, which included slashing 4,500 jobs and a revised second-quarter earnings forecast.
The company said it expects a second-quarter loss excluding items of 47 cents to 51 cents per share, more than the 27-cent per share loss it posted in the same quarter last year. It also expects revenue to decline to $2.6 billion from $3.1 billion a year ago.
The news savaged the company's stock value, with shares tumbling 17 percent on Friday.
"[The takeover] is the best thing that could have could have happened to you [as an investor in BlackBerry]," said Dan Niles of Alpha One Capital Partners.
(Read more: BlackBerry deal disappoints pro traders)
"When was the last time you saw a company of BlackBerry's size cut revenue forecasts by almost 50 percent in a pre-announcement?" he added.
BlackBerry's fortunes have certainly deteriorated in recent times. Shares have declined around 90 percent from over $80 per share in mid-2009 to around $8.82 per share as of Monday's close.
T3live.com's Redler said BlackBerry was on its way down and the move to go private was unlikely to change the firm's fortunes.
(Watch this: Can BlackBerry sort itself out?)
"The writing has been on the wall. [BlackBerry has] been trapped in a downtrend [since] well before 2013... They are lucky to get $5 billion. If they didn't it could be bankruptcy in six months or less," he said.
"[You] can't be a one trick pony... you can't survive. They had no apps or ecosystem, just like Dell, except for email etc. Then they were late on the iPad-type product," added Redler.
However, some investors must have viewed Monday's potential takeover positively, as the stock jumped nearly 5 percent before retreating slightly.
The owner of Fairfax Financial, Prem Watsa, is considered by many to be the 'Warren Buffett of Canada,' and a well-established value investor, which could have helped boost sentiment.
(Read more: BlackBerry buyer Prem Watsa an old hand at value investing)
Sanjeev Kumar at Delamore Consulting said earlier this month that if BlackBerry were to go private, it could unlock "serious value" in the firm.
"As a private company BlackBerry can focus on unlocking value from various parts of its business including the research and development driving the overall growth in revenues and profits going forward… In about two years' time the new BlackBerry will potentially look like a very different company and could provide a very juicy exit for the new owners. In short, there is serious value in BlackBerry," he said.
Fairfax Financial is not obligated to follow through on the agreement, and is currently trying to raise financing from Bank of America Merrill Lynch and BMO Capital Markets.
— By CNBC's Katie Holliday: Follow her on Twitter @hollidaykatie