I spent two weeks of my quarantine at Chisaki's and Tsukasa's place, and everything was great. The apartment is relatively large by the Japanese standards, with a big bathroom and a small kitchen area. The kitchen had everything I needed for cooking during my mandatory isolation period. The apartment is conveniently located in a quiet area about 10 minutes walk from the Sky Tree tower. There are multiple convenience stores in the area, as well as a very nice supermarket ("Life"), which is only about 15 minutes away by walking. A huge plus during the isolation period is that this apartment has a balcony, which allows you get some fresh air outside. The communication with Chisaki and Tsukasa was very easy and fast. They kindly allowed me to check-in earlier, since I arrived with an early morning flight. I would certainly recommend this place for staying in Tokyo.