The number of buildings built in large numbers from the postwar period to the period of high economic miracle is increasing as vacant houses due to the declining population. And, in the modern age full of things, sticking to "new", the purchased things will continue to be consumed and increase as waste. We are ending the "era of ownership" that was particular about "new", and we are going to the "era of sharing" with each other by utilizing existing things. We will use the vacant space of the housing complex to share things that are overflowing with our daily lives, and propose new encounters and ways of living in the future.