Battlefield Hardline

Episode 8

In order to get this trophy, you will have to employ some good sneakin'
The goal will be marked by a white circle on your minimap.

After you escape the underground silo where you were imprisoned, scan the trailer park to mark enemies.
Go down to the right and enter through the front gate and immediately hug the wall and walk left.

Go through the trailers when you need to until you reach two chatting guards beside a parked car.
You will need to duck through a trailer, wait until the third guard is away from them a ways, and crouch sneak over to the left. Disable the alarm box as you go by.
(If you see a white bar appear as you sneak by, you can click the left stick aka L3 and run past. The guards might go on alert but would at least not spot you and start combat.)

Keep walking against the wall and arrest the couple of guards you'll meet along the way.
At the back entrance to a 2-story double-decker trailer, arrest the guard, enter through the ground floor and open the weapon cache on your right.

You'll see this trophy pop up. Congrats!