http://www.ign.com/wikis/detroit-become-human/Spare_Parts
EXTRA SUPPLIES AND TRUCKS
Run over to the gatehouse marked ahead of you and move to the left side window that you can enter through. You’ll need to remain hidden from the guards and not be spotted.
When inside, you’ll see where the key you need is located, but there are guards nearby. While you can kill the guards, to remain stealthy you’ll have to cause a blackout in the area.
Look to the right to see the circuit breaker, and then pick up a screwdriver behind you on the shelf. You can use it to short-circuit everything and cause the blackout.
Open the glass and damage the circuit breaker, the guards will begin to move around once the lights go out. Make your way to the far left side to avoid their flashlights and pick up the ket on the table.
While the guards are distracted, make your way to the far left back side of the building and go through the window to escape the building without being detected.
Run back to the rest of your group and get inside the truck. Hit the prompts to activate the truck and you’ll escape the facility and head back to Jericho. There will be a cutscene showing the consequences of your actions and then the chapter will end.
Gatehouse additional choices:
1. Jump back outside and kick the oil drums to cause a loud noise to distract the guards away.
2. Grab the handgun and threaten the guards. A pretty neat QTE will take place.
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