Upkeep (Wealth): Charms with this keyword – which are almost always Municipal charms – consume resources in order to do whatever it is they do. Refining plants require fuel and harvested scrap, refectories require access to feeds of nutrient slurry, data-vaults demand continuous streams of rare fluids, and so on. Where as a charm that requires Crew can tax a city’s pool of manpower, charms that require Upkeep place demands upon its material resources.
Depending on his Wealth (Masters of Jade, Page 79), a city can support a limited number of Upkeep charms at any given time. A Metropolis is limited to a single charm with a Upkeep requirement equal to its Wealth, plus two charms with with Upkeep requirements equal to its (Wealth – 1). It may use any number of charms with Upkeep requirements two or more lower than his Wealth – their costs are trivial in the context of the city’s greater economy.
Allocating resources to a charm typically takes (Upkeep Rating) weeks as shipments and conduits are re-routed. Releasing allocated resources from a charm is effectively instantaneous, the time it takes being absorbed into the reallocation process.