Various fields of science require solving complex computational problems using resources of high-performance computing (HPC), high-throughput computing (HTC) or Distributed Computing Infrastructures (DCIs). Service oriented infrastructures based on Cloud paradigm simplify utilization of scalable on-demand unified sets of commonly used services. Virtualization and Cloud technologies based on Open Source solutions help to provide to researchers various variants of access to on-demand scalable resources from Private, Hybrid, Scientific, Scientific Federated or commercial Clouds. In the paper described the milestones and perspectives of deployment at the small joint IMI-RENAM cluster Open Source based Centre of Excellence with flexible internal reconfiguration and cost-effective access to unified sets of services.