M.B.
We've done one of these for an 8th birthday party. I agree with the nail polish and maybe lip gloss and some hair accessories too for favors. The dollar store or other discount stores will help you save money here. If you can get small makeup type bags inexpensively, they would make great goody bags too (we found some for $1 at Target). For a craft we made tissue paper flowers and had vases for each girl (also about $1 each). If you didn't want to buy the vase, you could just tie a bunch of the flowers together with a ribbon to make a bouquet. You may want some extra hands if you're planning on doing nails, hair, and/or makeup, depending on the number of girls attending. I know the hardest part for us was squeezing everything in. Have fun!