Advise for commercial on installments 1.8m-3.6m

Hi to all, thanks to zameen.Com who providing this forum.
Dear all, in next 3-6 years i want to buy commercial plot on installments, i can pay around 50000/month from today, can you please suggest which society is the best with this amount , where investment will be secure and be fruitful in near future. My location is islamabad.And can be anywhere in islamaabad. Jazakallaha