The real size of the BM foundation is actually a lot. I guess you get like 2-3 months worth of powder if you wear it everyday. But if you order it from the tv, you get three different colors so that you can mix them to get your skin tone. I guess the main colors are light, medium, tan, and dark and in each one of those you get 3 different shades plus a tan color, a blush type of color, and the mineral veil.
Those blotter sheets, you can get at like drug stores. They're small, so it just depends if you care or don't care about people seeing you blot your face with one of them.