i visit with my family to naran area on 28to 31 july 2009.
1- i think no need for booking from islamabad. they are lot of hotel where you can stay.
2- average rent for double room about RS. 750 to 2000 and more according to hotel condation.
3- you can stay at shoogran when you return from naran. and see seri paiya points.
4- A PTDC bus goes to naran on daily at 9.30 am From flashman hotel sadeer. where you can booking.