Nowadays, many companies expose their competencies as services on the Internet to facilitate the cooperation with their customers. This situation has created a new marketplace where services have been provided with similar functionality but different qualities such as cost, performance, and reliability. In this scenario, service composition providers have faced the challenge of choosing services that fulfill an expected quality without compromising a planned budget. This challenge is even more stringent when services have different cost behaviors. As a consequence, services can be less expensive than others in a scenario and be more expensive in others. Several approaches have been proposed to address cost analysis of service compositions. However, these approaches have not considered all classes of possible cost behaviors, e.g., Fixed, variable, mixed and step cost. This paper addresses this limitation by proposing a solution to analyze costs of service compositions taking into account service reliability and all classes of cost behaviors. In order to evaluate the proposed solution, we carried out some experiments that show its effectiveness.