You'll find something useful for scaring zombies away in the safe :) The code to the safe is hidden somewhere in the office, but you might need a certain item to find it!
What item?
Crowbar, look for it in the golfbag in the basement. (And here I tried to be nice but not spoiling too much :P)
It amazing game and I love the ending but what was in the box?
You should've gone back down into the basement when the lights were back on and you'd found out ;)
lolol very helpful