In the result of scientific and technological evolution in Software and Requirements Engineering fields many techniques, methods and tools have been developed to support our daily work. Most of them are more suited for big organizations and companies. Of course this is a positive development that brings value to engineering. But not always these innovations bring value to small or medium companies working on Information Systems development and support projects. A good example is the issues with requirements management in long term use of requirements and system. If we use agile methods, in most cases in practice, the documentation is very poor or limited. Another example is the waterfall method where the documentation is developed in the beginning of the project, but at the end of the project the requirements can be changed (in practice). This all can bring us to certain problems in future work. For example, how will we know the build of a certain system, how it must work etc. This work is focusing on requirements inheritance and availability issue in small and medium companies with heterogeneous projects