With the increase of data traffic in the global mobile network, the limitation in resources of data computing close to the edge is becoming an important issue to resolve. This article addresses the cloud radio access network (CRAN) in 5G HetNets architecture and proposes to take benefit of extra computing and storage resources in the edge to enable the offoading of a set of mobile user services from the remote cloud computing servers to an edge cloud computing infrastructure deployed next to remote radio heads (RRHs) to better serve mobile users and improve energy effciency. However, this architecture poses many challenges. The first one is related to the clustering of the various deployed RRH to better serve end-users. For that, we propose a two-stage RRH clustering mechanism in order to fully exploit the benefits of C-RAN architecture. The second challenge is related to the scheduling of the offoading. Therefore, we propose a cost-based scheduling scheme (CBSS) that aims to minimize the scheduling cost while considering resource availability in the infrastructure, resource requirements from users' applications, services execution deadlines, and load balancing. The proposed solution permits us to make better ofoading decisions and to improve the users' experiences. The solution was implemented in a simulator to highlight its performances and compare them with other existing approaches.