Integration involves the systematic linking of system components, functions and solutions. For digital systems comprising low-cost components, integration enables the sharing of resources and allows them to benefit from each others functionalities. However, in general integrating low-cost systems can be difficult, since data is heterogeneous and distributed over multiple sources and there is no common interface to interact with resources. This study proposes the use of reference architectures as a means of supporting such integration needs. Reference architectures are models that provide a structured template with common terminology and support integration through a systematic, repeatable framework. In this paper, we evaluate strategies to integrate digital systems formed from the same reference architecture. We first select three reference architectures and use them to conceptually design the integration of two low-cost digital systems based on different strategies. Then, the conceptually designed strategies are evaluated in terms of their effectiveness to be realised at low cost. Finally, the most effective strategy is deployed for an industrially relevant application, and validated by comparing its effectiveness to a system architecture driven integration. The evaluation results suggest that coordinators with a common service bus and virtual data integration are effective for integrating low-cost digital systems.