Cracking the Vault: Teamwork Required to Access Secure Room in Main Hallway

The vault is located in the main hallway and has a large metal door. You can enter through the back window or basement.
To open the vault, one player needs a keycard and the other needs to hit a button in the manager's office.
The keycard is in the basement, which you access by drilling/finding the code for the basement door.
In the basement's left corner is a lockpicked door with the vault keycard on a table inside.
Bring the keycard upstairs, swipe it at the vault panel, and hit the office button simultaneously to open the vault.

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