After finishing Paparazzo - The Partnership, there will be two green circles that appear on the map. Go to the one in Mirror Park to start this mission, where Beverly will call you and say he knows of some royalty in the area buying some drugs. He wants you to go and meet up with his contact, who should be nearby.
When you get there, the contact will say the target is behind the store and suggests you take a picture from the roof. Go to the left and find the fenced in area with a dumpster, which you can use to get to the roof. Once you get on the roof, find a good vantage point, take out your phone and snap a picture of the target and the other people.
Send a good picture to Beverly and you will most likely attract the attention of the bodyguards. If this happens, hurry up and drop to the ground, then grab a vehicle and start getting away. You should be able to cut through the grassy area and get away from them quickly. Once you lose them, the mission will be over.