A.,
Congratulations on being a stay at home Mom! That's so wonderful for your babies!
AIO will take you a while to realize the difference in not paying for disposable (and if you are sick, plan on disposables, bc you won't be doing laundry!)
I bought diapers, and covers, and copied a design for fleece covers (not as good as buying fleece covers - they are better material - I just ran out of outlay)
They are bulky. They're not as cute. They can up a clothing size.
I bought 2 days of diapers (so one could line dry while the other was being used.)
I had ONE box of disposables from Nov to August. We bought our 2nd box after having to take a trip that didn't have facilities for washing diapers (family home - you just can't make some people see how YOU are saving money by using their washer). I despised the ones I bought - a year ago this brand was GREAT and now they are skimpy. I prefer my cloth.
You will save $ over time - if you are diligent. I didn't buy the AIO because if I do have to start using the dryer, I didn't want to pay for something to deteriorate just because it was a little wet.
That's the other thing: You're (supposed to be) changing every time baby wets, not just when the diaper is full. So 12 diapers for a day is not totally unrealistic.
They're not (as) cute as disposables. But the savings I realized was roughly $40/month times 9 months. That's food on my table and 3 months covered the diapers.
I also bought the next size up. Buy the right size for your baby. Especially if your family is going to expand by one or two more. I doubt my son is going to BE in the next size up before he potty trains. He's just lean.
If you go diaper/cover, there's a saving over the AIO. Get your baby sized.
If you put your older babe in to cloth, line dry as much as possible.
I don't know what you buy for diapers. So I don't know how much you will save.
You can go to Luvaboos.com and see if she has the info on what disposables do to landfills. Not to mention the fact that waste is not supposed to go in the garbage in the first place - it's against the law - so technically you're not avoiding the emptying part in the first place.
The best part of disposables that don't get used before your baby sizes out of them is: you can gift them to a new Mom, or give them to a Mom who needs them. You can also return unopened boxes (usually, BRU gets sticky about that one and 90 days). .
Good luck!
M.