We spent three nights at Yu's place with three people during our two-weeks long Japan trip.
The apartment is super nice, right next to the Tokyo Tower.
The whole place is clean and modern with every appliance a traveller might need for a couple of days. Ideal for a couple, but there's plenty of space (and an extra bed) available for a third person as well.
Convenience store and metro station are just down the corner, while the nearest train station for JR pass holders is around a 20-30 minutes walk (or you can just take the metro to one for some change).
Yu was very welcoming and always responded in a couple of minutes when we needed some help, which was very reassuring.