There is a need for real estate lifecycle instruments to address the new regulations. So far, no instrument includes all sustainability dimensions in all phases of real estate, due to the heterogeneity of the underlying data. In addition, the leverage of the digital transformation in the sustainability transition is yet to be addressed. The aim of this study is how a meta-instrument should be structured to overcome the existing contradictory challenges in sustainability and to enable sustainable decision-making and management for real estate owners. This study examines this question by applying the following methodological approach: 61 literature studies were re-viewed, and concepts and systems were examined, which contain partial solutions at individual levels, be it for sustainability assessment, for the monetarization of sustainability aspects or for the maturity of technical systems. These instruments have their shortcomings as they only map individual aspects, but do not offer a comprehensive life cycle management solution for portfolio holders. Within the framework of this study, a new concept for a tool was developed, allowing to combine the various levels of real estate life cycle, sustainability, and digitalisation in a single holistic model. This multidimensional model was optimised using experts’ opinions collected in 2 workshops. The first results reveal the applicability of the developed instrument but remains difficult to manage by potential users. The novelty of the approach comes from considering the entire life cycle, technical and management processes enabled by digitalisation.