My partner and I stayed at Yumi's place for 10 days on our first visit to Tokyo.
It was overall a pleasant stay.
The location is fantastic: it is easy and fast to arrive when coming from the Narita Airport, close to a metro station, and plenty of restaurants, bars, and convenience stores in the surrounding area.
The flat is small but it has all you need and it is kept in good condition. The thing we missed was extra towels plus some extra essentials. The flat features a washing machine and clothes hanging is provided too.
Yumi was always available and quick to reply. Thank you for everything!