Turn around when the mission begins. Look near the ammunition crate to find a 
  phone.
  Enter the parked trailer in the alley. The phone is on a crate.
  Continue after the parked trailer, and unlock the door. Look to the left when 
  you enter to find a phone.
  Enter the outdoor parking garage with a white truck and two parked trailers. 
  The phone is in one of the trailers.
  Get on the rooftop, and walk to the left side. The phone is next to the red 
  pipes.