Reply to your query is:
3 days plan is enough. I recommend public vehicles, but choice lies with you.Driving is not easy on Malam jaba, White palace, Kalam and till Mahodhand routes.
Reach Mingora through Irfan niazi coach Daewoo (timings:7 pm, 8pm and 10 pm....three buses).
Day:01 Malam jaba visit + Fiza ghat park........ Night stay at Mingora.
Day:02 White palace visit + Swat museum...... Make a journey towards Bahrain(night stay).
Day:03 visit to Kalam, Ushu valley and Mahodhand......Departure for Lahore.
Notes:
1. Check in hotel after 12 pm. Have a breakfast at Mingora in the morn, then take rickshaw and move towards Malam jaba. After asir prayers, return back to Fiza ghat park. Have hotel room either near to Mingora main bus stand, green chowk or sabzi mandi road where prices of rooms are lower than Fiza ghat park hotels...... and take rest.
2. White palace is 30 minutes route from Mingora. 2 hrs are enough to go and come back to Mingora. Visit Swat museum that is of only 1/2 hr duration trip.....Take van and go to Bahrain.
3. Hire car from Bahrain(around 5 to 6 k) to Mahodhand and back. It is 5 hrs journey on one side. You may easily return back till 5 pm. Go to Mingora and depart to lhr by I.K.N Daewoo coach by 8 or 9 pm......
4. Make an estimate of expenses yourself by going through following FOUR threads:
CHEAP AND SAFE SWAT TOUR IN 2015.
MY SWAT TRIP HIGHLIGHTS- JULY 2015.
SWAT TOUR TO USHU AND UTROR VALLEYS.
A JOURNEY PLAN OF SWAT VALLEY TOUR.
I think it is around 25 k. All the variables are not fixed; they are according to my view:
Travelling:12 k;
Stays:3 k(2 nights);
Food:4 k;
Tour(Bahrain-Mahodhand):5 or 6 k.
5. Talk to Wali khan and Javed taxi drivers whose contact numbers are given above to arrange room and car on rent for you from Bahrain. they are nice fellows to be accompanied with families; if they become handy for you.
6. About Kundol lake, quaidan is absolutely right.
7.Fiza ghat is park constructed by Japan as a good will of friendship to Pakistan along Swat river in Mingora.
REGARDS