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This shouldn't prove to be too difficult. From the time that you get to Rhonda's Garage, you will start getting calls from a mysterious stranger. He will give you multiple side missions for each chapter. Aim to complete them before completing your main objective, as the missions are on a timer. If the timer runs out, you automatically fail the mission. I personally got this achievement sometime during Chapter 5. So if you do happen to miss a few, you will still have plenty of opportunity to obtain this one before the end of the game.