so i will try to explain this the best i can. So i noticed that a few things where doubling up ex when i buy a door i pay for it twice and everything thing else you buy, when i use the box there is two guns, when i buy a perk i get the perk i con twice! if you want more detail add me on skype: xXfatboyproXx
Hmm, similar happened to me a long time ago. Everything was doubling but in a different way.
I don't know if you have the same problem as I had, but why it doubled everything was because that somehow I had accidently called zombiemode twice in mymapname.gsc, so I had two lines of So I just simply removed one of them, and it worked. I had zombiemode called twice which doubled everything whatever I did in my map.
So go to yourmapname.gsc and see if you maybe have accidently added an extra line of zombiemode and delete it. Or maybe you have accidently called zombiemode in an another script somewhere?