what is considered good offer for family of four in Istanbul?

Hello, I was offered a job in Istanbul, and I have a family of four, what is considered a good offer? My two sons are 4 & 8 years old, I've looked into the international schools which I find extremely expensive, will I find a public or private school teaching in Arabic & English with a reasonable fee? what is the average monthly budget needed for grocery, food, living..? what is the cost of rental apartments not far from Bahcelvlier? Would my wife find a job there/ part time job? I come from Jordan, and both my wife & I are engineers. I appreciate your help, thank you. Tamer