I agree with much of what previous posters said. We started off with gDiapers (small) and then small-sized Fuzzi Bunz which were big on DS at ~5 weeks but lasted him until 6+ months (he's on the smaller end). I would start with just enough to get you through the first couple of months until you get an idea of what your LO is like in build and size. The small FB fit our son great and we loved them then, but the medium ones less so now that he's bigger. My current favorite is the BG 3.0 for my son's build & size. I wouldn't stock up too much right away because there are always cool new products and prints coming out - part of the fun is seeing all the new stuff coming to market, and then getting it! (Which is harder to do if you've already blown your budget on all of one brand/model.)
Is there any reason why I wouldn't want one-size CDs? - Page 2
We use the sized fuzzi bunz but this is what I've read.
Adjusting the diaper can be a pain
Heavy rotation will generally cause the diaper to wear out pretty soon; BG velco almost always wears out before you outgrow them; you can save money buy buying used sized diapers AND reuse them for the next kid
You get a lot more bulk in the begining
Kids change a lot and so you can end up with your "investment" not working
Infants don't fit them and big kids will outgrow them before potty learning so you can still be stuck with buying three sizes
Almost all of my purchased used FB were 1) used 2) used by my DS 3) lent to another baby and 4) will be used by next baby. That is pretty awesome value.
My larges are the same way.
THe mediums have the most use so maybe they'll only last three kids and not four.