we had 3. because 4 would have just been stupid.
just realize that after 2 the work increases exponentially. 3 are not just 50% more work than 2, it's more like 3 times the work to add the 3rd kid and it increases the more you go. be very careful adding that 3rd kid, thats the point where they now outnumber you.
the real question isn't the number though. it's the when to have them. my first was born when I was 19. on one hand that was very hard financially. I have friends who's kids are very young and they don't have near the problems we did with school-cloths and general kid expenses.
on the other hand my youngest graduates in 3 years, while I have friends I went to HS with who's youngest is less than a year old. they'll be in their 50's when they get teenagers (ha ha ha ha ha ha ha ha ha, that should be some show) while I'll be getting a break soon.