I have spent many hours trying to figure out all of this. I will give you my base lines for what I feel things will cost.
Start up baby needs (assuming I pay for it all and no one gives any gifts, all new) $3,500 ( I have this list if you want to see it but it is long, some things are not needed but nice wants)
Monthly baby items for the first year (breastfeeding, Costco cost of diapers) $200 (I have seen some people only spend $100 and some $300, depends on how you live)
Daycare? (I am hopping so stay at home, but who knows)
Savings for birth and health care = look at your insurance plan, mine covers it all but the average vaginal birth and typical nursery stay runs about $14K, if your insurance only covers 90% or 80% then you want to have the 10-20% saved up.
Savings for maternity leave = 9 months my share of cost of living, at least. You never know when you are going to be put on bed rest. I am a healthy average young 20 something female and I spent 3 weeks on bed rest in the first trimester before I lost the baby. It would have been at least the whole first tri, to then be re-evaluated when I hit the second tri. I was allowed to be on modified bed rest, only going to classes, it was my last 4 weeks of college, had I been working I would have been on full bed rest. You want to have enough saved up to make it through any bed rest and then maternity leave. I say 9 months to cover 2nd and 3rd trimester bed rest and then 3 months of maternity leave.
Some suggestions I have:
If you or your DH are going to stay at home, then try it out for one year. That is living off of one income for one full year and just put the second income in savings. This gives you a chance to get use to only having one income, while having a safety net for when you don’t plan right. Plus you have a huge savings then.
If you are debating between staying home and working, look at ALL the costs involved. Add up what you spend on work in one year, car expensive (oil changes due to miles driven, new tires from the miles, higher insurance, gas) food costs (eating out for lunch) work clothes, ect. and then add in daycare cost and formula cost. Compare this to your income, how much do you have left over, is it worth working for? Then considered that if you don’t work you can cut major costs, like cheaper insurance because you drive less, less car care, less gas, less money spent on work clothes, ect. For some people they is only a $100 - $300 difference, and they can make that up by decreasing costs or working a part time job on the weekends or a couple nights a week.
WOW, this is a very long first post