I have the similar amount of mortgage

as yours ( even house size), and in 5 years I should pay off. However, after carefully calculation, I am even reluctant to put my 2nd kid into a private school. Money is the big concern. With one kid in college, which is my priority, I am not sure I can handle the tuition for another kid in private school if the economy goes worse. The college cost could be big. For your case, even I don;t have the numbers, my guess is that you might end up paying 2K-6K monthly.

Good luck!