One way of understanding what things cost is to imagine them as sacrificial rituals.
Blood doping is a sacrificial ritual whereby a drop of blood is permanently sacrificed for a future drop of blood.
Meetings are a sacrificial ritual whereby multiple victims are simultaneously suspended in purgatory for a length of time, to summon a demon with the sum of their knowledge, but intelligence equal only to that of the average member, divided by the number of victims.
Employment is an sacrificial ritual whereby the subject is imperfectly enthralled for the bulk of their day by a demon, and in exchange receives a substance that may itself be sacrificed to enthrall lesser demons through economancy, with powers proportional to the amount of substance used. Many wizards use an even powerful spell called Full-Time Employment, in which they commit to a long period of enthrallment in exchange for a more than proportionally larger amount of the enthralling substance.
Many other economantic spells have a similar structure to this.
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