You cannot get away with using the simple output filter, since it cannot do accounting. See section Filters . Whenever someone prints a job, the filter logs the user, host, and number of pages to an accounting file. Every month, semester, year, or whatever time period you prefer, you collect the accounting files for the various printers, tally up the pages printed by users, and charge for usage. Then you truncate all the logging files, starting with a clean slate for the next period.
Timely accounting is less common, probably because it is more difficult.
This method has the filters charge users for printouts as soon as they use the printers. Like disk quotas, the accounting is immediate. But this method requires some database code to track users and their quotas. For example, you choose whether to use periodic or timely accounting. And you do so by modifying the filters to save this information.