My colleague and I stayed here for one month when we first moved to Japan. The apartment is very clean and tidy, and the location is great, with loads of cool bars and vintage shops around.
It's extremely convenient for Koenji Station, and about a ten minute walk to Shin-Koenji station, so it is well connected. There is also a 24 hour 7-eleven right next door.
The apartments has one bedroom and then the tatami room with space for several futons. It was spacious for two people. There is also a fridge, washing machine and space to do a little cooking.
Miyu is very kind and was very quick and helpful when responding to any questions we had.
It can be a bit loud at night due to some of the bars, bur overall a great place to stay! I already miss it!