@mri1977
well, that depends on the usage of ur car.if it sits in ur garage most of the day, doing just 10-30kms daily in clean islamabad like dust free enviornment, it may not require a wax before 2-3 months.
on the other hand, if its driven even the same 10-30 kms in a dusty place (dust scratches the smooth finish of the paint) then it would require waxing every month.it depends on u now.
a simple rule to know if u need waxing on ur car is that, when u wash it, water droplets should stay on the surface as indivisual drops, they shudnt be in a continuous surface,if they are, its time to wax the car.