method and system for allocating predictable costs for consumable items of a laser system includes determining an average or predicted lifetime of one or more components of a laser system . then , costs are estimated for the repair and / or replacement of the components in advance of their predicted failure . the costs are then scheduled to be paid at a known time or known times . the average or predicted lifetime may be determined in terms of time , pulse count , accumulated energy input to the discharge , number of workpieces processed or another countable parameter . also , the component or components predicted to fail may be ordered in advance for rapid delivery at the time of failure . the components may include a laser tube , tube windows , a line - narrowing optical component , a line - narrowing module , a monitor optics module and a halogen filter , the pulser module for a gas discharge laser and / or containers of laser gas .