Dominant agri-food systems are increasingly seen as unsustainable in terms of environmental degradation, mass production or high food waste. In an attempt to counteract these developments and foster sustainability transitions in agri-food systems, a variety of actors are engaging in socially innovative models of food production and consumption. Using a multiple case study approach, our study examines three contrasting alternative economic models in the city of Berlin: community gardens, the app Too Good To Go (TGTG), and a cooperative supermarket. Based on 15 qualitative interviews, we provide insights into their transformative potential by exploring participants' underlying motivations, the changes they have experienced, and the challenges and potential for future development of these models. We find that participation in community gardens and the cooperative supermarket is similarly motivated by social aspects and dissatisfaction with existing food access options, while TGTG users are more motivated by financial reasons. Our study shows that change is experienced mainly at the individual level, e.g. by building new relationships, changing cognitive framings, and learning (new) practices, especially in community-oriented settings. The individualization of change shows that these models have a rather low potential to lead to more systemic accounts of changes. Yet, they can prefigure regime change, describe resistance, and foster cumulative incremental change that may spill over into society. We conclude that in order to sustain this role and drive transitions, it is important to up- and outscale these models; and we provide recommendations on how these models can mutually support their development, establishment, and protection.