Member States shall make best cost-effective use of national financing and financing available established at Union level, in particular the Recovery and Resilience Facility, the Social Climate Fund, the Cohesion fund, InvestEU, auctioning revenues from emission trading pursuant to Directive 2003/87/EC of the European Parliament and of the Council (
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) and other public funding sources. Those funding sources shall be deployed consistently with a path to achieving a zero-emission building stock by 2050.