The effort of all service providers is to maximize their revenues. The ideal case would be, when a service provider obtained payment for entire services provided. But it is not always possible. Some services may not be paid for. Distribution companies (electricity power, gas, and water), transport companies (airlines, railways, buses, and taxis), telecommunication companies and companies established by the government (e.g. cash of road tax) represent such type of enterprises. Their clients pay for the volume of drawn media, distance of transmission, service duration, amount of transmitted information or travelled distance. Most services are charged fully, but certain services are only charged partly or not at all. An appropriate theory concerning the service provision effectivity and charging policy will be done on examples from telecommunication business and from road tax cashing.