CNG, Trakker and Rims dont get you extra money for your car. If you say you have rims and trakker, buyers would say that they dont need it. If you say you have CNG, they would say that the engine must be damned till now.
If you say you dont have CNG, buyers would say that they need a CNG fitted car and if they have to buy CNG other than the car then it would cost them higher than the market.
Bottom line is that, majority of the buyers talk weird and they are desperate to devalue your car and get it for the cheapest possible rates.
My advice is that you get the market value of this type of car and then sell it to the highest offer without waiting. (i have had pathetic experience 3 months ago when i tried to sell my Corolla GLi 2003 immediately). Best of luck
btw karachi's market is low.