1) Here is a rough itinerary I made for you:
Day 1: Leave Lahore 6 AM, reach Naran by evening, night stay in Naran Hotel
Day 2: Leave Naran, visit Jalkhad, Lulusar, Babusar and reach Chilas within daylight and stay in Chilas Hotel
Day 3: Chilas to Raikot Bridge, Raikot Bridge to Tato via Jeep, and Tato to FM trek. Night in cottages
Day 4: FM to Base camp and back to FM for night
Day 5: Return FM to Tato trek and Tato to Raikot via Jeep and advance to Gilgit for night stay
Day 6: Gilgit to Attabad Lake and in return visit Baltit, Altit, Duikar, night stay at Duikar or Karimabad
Day 7: Start return journey and reach Thalechi before 10 AM to catch up the convoy as they don't allow Hiace without convoy. Night stay could be at Besham or (if the driver is fresh, you can continue to Rawalpindi and Lahore but not recommended).
Day 8: Besham to Rawalpindi and then Lahore.
2) Hiace will charge around 4000 Rs per day without fuel.
3) Raikot to Tato and return is 6000 Rs this year per jeep. May be a little increase after current increase in diesel price.
4) In Naran, you will be able to find budget rooms as its not the peak season. In Chilas, you can stay at Panorama Hotel, we stayed there last month and they charged 1400 per room. Gilgit, Hunza & Fairy Meadows are also very economical. I like Raikot Sarai at FM.
5) Open but anything could happen anytime so keep updated before leaving.
6) A Lahore based Hiace driver Hassan (03237500039). We hired him few times and has a neat/clean vehicle with powerful engine. You will only need to hire Jeep at FM which can be done easily on the spot. No need to pre-book.
7) Yes enough, Just drop the Sost from your itinerary as its not worth much if you are not going to go for Khunjerab Pass.
8) Security is quite ok. I came back from GB couple of weeks ago. Try to avoid night traveling.
9) KKH is ok. You can catch KKTF escorted convoy at 10 am at Besham and in return 10 am at Thalechi
10) Warm clothes, good trekking shoes, usual first aid box etc. Arms etc not needed for security.
11) Weather would be pleasant. Go for it.
Good Luck. Anymore questions, feel free to ask.