What do people really mean by administrative costs? Is it just an umbrella term to actually get money from a person for no real costs, just for a service? Or it includes really some expenses?
Administrative costs is an umbrella term for many different types of expenses, some of which may include an administrative assistant's or any other staff's time to process documents and/or materials used in processing said requests / documents (e.g. paper, ink, amortization of software and hardware, etc).
Pricing methods varies depending on the intent of charging an administrative expense in the first place. Some methods involve calculating the real cost and charging a portion of it, all of it or all of it plus a markup. Other methods may simply put a price high enough to discourage the use of said service when it must otherwise be provided.