The baby powder's average cost depends on so many factors and the company producing that particular powder brand. Further, it depends on the ingredients or material used. Whether it is an organic baby powder, a natural one, or even synthetic-based powdery particles, it also depends on the weight and if it is Talc-free or a Talcum-based powder, fragrance-free powdery particles. Averagely, you can get a 425g talcum powder from $4 and above. You could also get a relatively cheap organic baby powder such as California baby calming organic powder or era organics.