Cities face the challenge of addressing urban vacancies due to market volatility, rapid shifts in needs, demand, user preferences, or issues related to financing, planning, or delays in building approvals common in cities like Zürich. The study delves into a transformative shift in the Swiss real estate market, emphasizing the integration of circular economy principles, impact investments, and digitalization. The research approach is mainly descriptive, drawing upon case studies of temporary use urban projects. It incorporates a review coupled with the application of design thinking in the development of a digitalization model. In Zürich, the temporary use of vacant buildings is predominantly as office space showing a limited multi-scalar impact. In contrast, in vacant sites, Nature-based Solutions interventions demonstrated high multi-scalar impacts, enhancing biodiversity, air quality, and resident well-being, and aligning with circular economy principles. Meanwhile, various flexible uses of vacant sites indicated moderate impact, promoting innovation and new business models. A digitalization model is proposed to re-purpose these sites in circular rather than linear economy. The research underscores the importance of temporary, flexible uses on vacant site as platforms for testing new multi-scalar impact investment ideas and establishing the financial profitability of nature-based solutions in urban contexts. The study highlights the potential of temporary urban land use to promote swift urban transformations, balancing financial returns with ecological impacts for advancing circular economy.