Twelve buttons make one order. I think that is plenty for any outfit. A blouse will take 6 or 7, and the others can be used for other pieces to go in the set you make. These were my favorite buttons for my doll clothes.

Here is a little tip: get a kid's washable glue stick to use when it is time to put buttons on. Just rub some glue on the back of the button and stick it to the fabric where you will be sewing it on. If you have a button sew-on foot that is ideal because it is nice and flat on the bottom. When you sew the button on use a zig-zag stitch, adjusted for the correct width (guide it with your hand, go slowly here) and with zero for stitch length. If you hit the button hard with the needle you will break it and just have to throw the pieces away. The glue stick has made my sewing life so much easier!