[aantix]

Gross 500K, you're probably working with 300K after Fed/CA/SF taxes..

138K for rent.

76K for childcare if all four (might get a nanny cheaper)

Student loans because you both went to an Ivy League

Two cars, cell phones, real organic food, savings..

Maybe one big family vacation.

It adds up.

You won't be flying to Paris every weekend on a private jet.

[manfredo]

For married couple you'll still be looking at 320,000 in post-tax income at least - probably more if you have 4 kids. The rent is an over-estimate (6 bedroom house in central SF) and can easily be reduced.