Elves do not rely on money in the same way humans do. While money is exchanged for goods and services, it is not a driving force in their society and is not a factor when considering social classes or nobility. Elves are given a birth fund with enough money to support them through life and maybe even another one. They do not have to work like humans do; they choose to work because it is an interesting thing to do with their very long lives, because otherwise they would basically do nothing their entire life. Each birth fund is 5 million lusters, with 1 luster equal to about 1 million human dollars, making each birth fund worth about 5,000,000,000,000 human dollars. Although most elves get their fund at birth, Sophie received hers when she first arrived at the Lost Cities in Book 1: Keeper, as she was born in the Forbidden Cities to a human family.