If you can find a Motorola Moto G 3rd Gen, it's the best option. In Android world, Motorola is one which works on principle of iOS and iPhone, that is it's all about experience. Camera is good, and it is also water proof (can survive if dipped up to 30 minutes in water, over cetain depth).
Unfortunately, Motorola phones are not that easily available, but since you are in karachi, you have fair chance to get one.
Other options include Samasung Galaxy J7 (~28000 PKR), HTC Desire 820 (~25000 PKR), Sony Xperia Z (~30000 PKR)