I've only kept track of the amount of times i was certain i was the first one in the office, its my first go-to position on two different spawns on Customs. If i wasn't certain if i was first or not, i didn't count the data.
Run 1: 2 folders
Run 2: 1 folder
Run 3: No folders
Run 4: 1 folder
Run 5: 2 folders
Run 6: No folders
Run 7: No folders
Run 8: 1 folder
Run 9: 1 folder
Run 10: No folders
Run 11: No folders
Run 12: 2 folders
Run 13: No folders
Run 14: 2 folders
Run 16: 1 folder
Run 17: 1 folder
Run 18: no folders
Run 19: 2 folders
Run 20: 1 folder
Run 21: no folders
Run 22: no folders
Run 23: 2 folders
Run 24: 1 folder
Run 25: no folders
Run 26: 1 folder
Total possible folder spawns (as tested in offline mode) is 5 different spawn locations. I'm not sure if there's a chance for more than 2 to spawn, but i've never found more than 2.
Average folders per run: 0.81
Chance of finding a folder: 57.7%
Few more things i found out on this location:
High chance of finding ammo in the room beside the opened door on the side near the RUAF roadblock. Frequently found 120 pc BT and SNB packs, combined with the loose spawns in the USEC consctruction site(the one with the grenade/machine guns) makes it a terrific spot to hit for low lvl players that need decent ammo.
You can sometimes find a bottle of alcohol on top of the cabinet next to the door that leads into the showers and on the desk in the room with the ammo next to the open door.
Very high chance of finding Salewas all across the building, good place to hit for Therapist's first quest once the wipe comes
The medicine room across the office with the folders frequently spawn morphine on the tables.
A razor headphone sometimes spawns on top of the filing cabinets behind the desk.
