There is an imbalance of control over personal data between service providers and civil society. While service providers acquire knowledge and influence individuals’ behaviour through data, individuals do not own their data, and the personal data ecosystem lacks the transparency necessary to be understood. The #digipower investigation explores the practical realities of power and influence in the data economy. This report, one of two, is a detail-oriented report examining the experiences of 15 high-profile participants (among them members of the European and Finnish parliaments, EU and Finnish civil servants, NGO directors, and journalists) in exploring their own personal data ecosystems. Each participant targeted around six companies, selecting common service providers they use in their daily lives, and were coached to use Subject Access Requests, data download portals and technical audits to obtain personal data and data handling information from those targets. Obtained data and responses were discussed with coaches and subsequently analysed by experts at Hestia.ai, who then used the collected data and the participants’ experiences to understand and map out patterns of data usage by the service providers. With over 83 individual/service provider relationships explored, we present four overarching case studies, illustrated using participants’ experiences and data. These case studies focus respectively on (1) influences by service providers on the physical world, and (2) the online world (2), on influencing by infrastructure providers (3), and on the challenges of obtaining held data (4). Through this investigation we contribute a pedagogical approach for research and examination of data economy practices, and provide a map of some common data flows between companies. Our accompanying narrative report takes a top down approach to map out the uncovered mechanisms of influence and power we reveal in the data economy, and considers their societal implications. The other report is titled "Digipower Technical Reports: Understanding Influence and Power in the Data Economy" and available at https://doi.org/10.5281/zenodo.6554155.