By GTA-series standards, mission difficulty in GTA IV is pretty well-paced. But we'd be happy to bet that you'll fail certain missions a few times. What you need is a video of the toughest missions being completed so you know the best way to success. We've beaten the ten hardest missions (as voted by a panel of 'experts') on video for that purpose.
The missions covered are: Snowstorm, Three Leaf Clover, Hostile Negotiations, Late Checkout, Union Drive, Diamonds Are A Girl's Best Friend, Museum Piece, No Way On The Subway, If The Price Is Right, A Revenger's Tragedy
2) Three Leaf Clover
3) Hostile Negotiations
4) Late Checkout
5) Union Drive