One parent staying home for about two years, who had a low salary, factoring in lost retirement contributions, is about half of that, we could have cut that part to $30,000 or so if not for that, true. That’d drop my (conservative!) napkin math to more like $130,000.

About $15,000 for the pregnancy and birth (we split it over two deductible years—whoops, didn’t make that mistake again). Daycare costs for the rest of that time, tens of thousands more. Probably $3,000ish a year (maybe a bit more) in extra medical spending on average (copays on check-up visits, added insurance costs, medicine occasionally, a couple visits that involved stitches or an x-ray over that time span)

That’s before food, clothing, furniture (you do kinda need a bed at some point—we go pretty cheap on furniture and clothes, but it’s still probably $3-4k over that five years, mostly clothes). Diapers (or a lot of extra power use, though sure, cloth diapers would have been net-cheaper anyway). Adds up.

So yeah, it was certainly over $200k for us (conservative estimate). Could have gotten it down to merely over-$130k by putting a weeks-old to 2-year-old kid in daycare, but we didn’t, maybe we should have.

[edit] I should add that it does get better after the first one; there are efficiencies and shared costs (daycare may give you a discount, even!). Getting all three to age 5 wasn’t $600k, probably closer to $400k. You also can do it cheaper, yes, but our choices were ones that nearly anyone who can at-all afford it is gonna make, like having one parent stay home the first year or two, going to all the medical check-ups, moving to an area with good schools (if you don’t already live in one), et c.

So 130K in opportunity cost?

No that would have been raw spending. The difference was about $70k in imputed wages because of what we chose to do (which, again, I think almost anyone who can remotely afford not to send a kid to daycare in that first year or two, will have trouble not making that choice).

Because these costs are so front-loaded, so tend to hit earlier in one’s life, you really don’t want to start doing a more-expansive opportunity cost accounting, unless you want to get depressed (I have. Trust me, don’t—sigh, so long very-comfortable-retirement-at-55!).

130K in raw spending in 2 years...on what?

Five years. Health care, child care, and everything else. At least that much. Child care would be about half of that.

Average day care in bay area is already 2500, before feeding and clothing the kids, or any after school activities.

And that's the most expensive place in the country, no? Most people don't live in the Bay area and if you need daycare, it's presumably because you have a well paying job and it's a tax deduction.