Despite the increase in vacant houses in Japan, existing owner-occupied vacant houses are not sufficiently converted into rental housing due to homeowners’ anxieties in legal and economic matters. In this study, we explore cases of the housing projects introducing sublease partnerships of owner-occupied houses; the projects by the municipality as a PPP collaboration and the projects introducing a lump-sum payment of a rent as a purely private business. These projects are found to have succeeded in dispersing among parties the costs and the risks a homeowner would take by achieving the three conditions; (1) A deal including renovation work, (2) Fixed-term lease contract and (3) More credible contracting party. The sublease partnership has the potential to convert owner-occupied houses into rental housing. However, some challenges which limit the sustainability of the partnership are pointed out.

尽管日本的空置房屋有所增加，但由于房主对法律和经济问题的焦虑，现有的自住空置房屋并未充分转化为出租房屋。在本研究中，我们探讨了房屋项目引入自有房屋转租合作的案例；市政府作为 PPP 合作的项目和引入一次性支付租金的项目作为纯粹的私营企业。发现这些项目成功地在各方之间分散了房主通过满足三个条件而承担的成本和风险；(1) 包括装修工程的交易，(2) 定期租赁合同和(3) 更可信的合同方。转租伙伴关系有可能将自住房屋转换为出租房屋。然而，