Honestly, Im personally not too fond of the far off areas that they are not trying to incorporate into Islamabad. They are still affordable though. The development work there is slow. We had a plot in one of those new sectors, based on a residential govt employee scheme, but we sold it recently for just 5lakhs, because property in those areas never spiked due to the distance from the city.
The best places in Islamabad to live IMO are F-7, F-8, F-10, F-11, E-11 and I-8, and they nice thing is, they are inside the mainl Islamabad and are the poshest places in the city, and give you the peaceful feeling of living in the burbs, because of the way they were laid out. The markaz idea in every sector makes sure that theres no illegal encroachments or business popping up inside the residential areas.
*If I magically get about 50 crores somewhere, I would buy an amazing house in E-7 or F-10 right away! *