I have saved a ton of money by cloth diapering! I use mainly prefolds (Green Mountain Diapers) and covers (Blueberry Coveralls). But I like to have a variety in my stash. I also have some pockets (my favorite are the Bum Genius 4.0), and fitteds (WAHM brand, Twinkie Tush). I have been able to use my diapers for 2 children now and some of them I will be able to sell after my second is out of them. They retain a good amount of value if you care for them correctly. I'd say a good stash would have anywhere from 24-36 diapers. It depends on how often you wash and how often your little one goes. I was about every other day and this amount has worked well. Our water and electricity bill went up when we started but not by much and certainly not by the same amount we would have spent on disposables!