Sry for late reply as i couldn't visit PW much in past days.
Isl- Shogran will hardly take 6 hrs if travelling with such large group so u can easily visit Sri Paye in the second half of the day. Just start earlier from Isl and enjoy the sunset or atleast late afternoon at Paey as that is the best time of the day.
Second day, reach Naran and visit Saif-ul-Muluk after getting hotel and lunch. Very easily manageable. Open air dinner will be fun as suggested above.
Use third day for visit to Lalazar, Jalkhad and Lulusar Lake. If you want to go to Babusar Top then drop Lalazar or atleast keep it for afternoon. This is very much a routine one day activity and will take even less time as road construction speed last year was unbelievable.
Return journey - Tea at Kiwai waterfalls and lunch besides Kunhar river in Balakot area will be fun on way back. Keep the day relaxed as u can start a bit late as well.
1- Coaster will take 6-8K minimum per day. I will not be surprised even if they ask 10K this year in June as June will be peak season before Ramadan.
2- Keep a budget of 20K for diesel as if u refill ahead of Balakot, u may get it expensive as compared to normal prices
3- Food will be 800-1000 per head per day if u eat good breakfast, snacks in day time and a good dinner in some good restaurant. It includes all other stuff as well like mineral water bottles, refreshments, on way purchases etc.
4- Hotels will be expensive .... rather very expensive. Sharing rooms is best option and try to get bigger rooms like in Lalazar Hotel where even 10 people can fit in one room. 2000 per head hotel budget is good estimate.
5- Zahid bhai's no. is already mentioned above or u can contact Qari Ahmed Rashid on 0345-9469770, 03229902476
Jeep budget has to be around 1500-1700 per head. This include estimate for Shogran - Paye, Naran-Saif-ul-Muluk, Naran- Lalazar - Babusar and back.
Expense u can calculate based on above information.