There's no way around it: pricing is confusing. It's a little like going into the gas station to pay... you can 'fill her up' or put $30 in the tank.  Most people spend $30-$40 for one hand, to a bit above the wrist. Larger pieces take longer (or use more materials) and therefore cost more. There is a balance between the time it takes to do the artwork, and how much materials cost. This is also why jagua costs more than henna. The materials cost of jagua is higher.