Re: Diaper pricing
I do not think there are guidlines because people are all over the place with prices. I have even seen prices of more then they cost brand new! In my experience I sell and buy only at 50% or less of the new price. That is ppd, shipping included. My items sell very fast that way. Really popular diapers you can get more on. Also hot prints that are hard to find will cost more. Wool is always expensive and close to retail price.
It is unbelieveable that people want almost asking price for a pooped stained, holey, loose elastic diaper. I always ask for a lower price if it doesn't say firm price. Almost everyone does. Sometimes I will accept a lower price and sometimes they are too low.
There are great deals to be had. Just look often. Ask lots of questions and ask for more pictures if there are not enough. Good luck.