The move towards a circular economy brings a range of practical challenges for product and service designers that will need to facilitate this transformation from a linear take-make-dispose model to a more circular model. The concept of Product-as-a-Service (PaaS) emerges as an innovative business model capable of catalyzing this fundamental shift. In a PaaS context, any product will be used by several different customers during its lifetime through different operational methodologies and value delivery mechanisms, so incorporating circularity into both product and service design is pivotal for the establishment of more sustainable product-service systems. To facilitate circularity, it is imperative to be able to close loops in the current PaaS offerings by the development of reuse, refurbishment, repair, remanufacturing, and recycling. However, different challenges arise from each of them, which translate into different design guidelines. With the help of the literature and through a cooperative ERA-MIN project, different expert partners provided their insights on the proposed PaaS offering for electrical and electronic equipment (EEE). The objective of this paper is to present the main challenges and describe the design guidelines derived from them.