Moving to Istanbul

Hi All,
I have recently applied for a job in Istanbul and am starting to research life there. I have spent several months in the city, but only know it as a "tourist" of sorts, not as a resident. I also have a 14 year old son who will make the move with me should things work out.
I am wondering if anyone could pass along any advice or tips or resources about living in Istanbul - avg. cost of living, housing, healthcare, etc. I am also starting to research English speaking high schools for my son and if anyone has any recommendations that would be wonderful.
My son and I have always lived close to my family and this will be a big change for both of us. If anyone could or would share their experiences of relocating their families, I would be really grateful - as it appears at the moment to be equally exciting and daunting.