I ordered 3 items on 11/11,one of the item arrived three days ago but duty charged was 3200, item cost was 3000,i returned the item and went to faisalabad GPO to custom guys, they told that since on parcel "car alarm" is written we are advised by seniors to charge high for car accessories to discourage the imports, I asked what code you have used he showed me the code which was related to car parts, I told him it is not the related code, he said we use the same and you will have to pay. He also told that prices written by senders are ridiculously low so we make assessment ourselves and accordingly apply duty, he also told that we check the item on net also. I had no choice so I paid but I think that if we ask the seller to write nothing like car accessories or router etc then they may be got dodged and charged less duty.
It is luck how much duty you are charged, in my last order of 9000 I was charged only 30 rupees 