This place has three rooms, but I'm not sure if the third room is in use. It's quite a modern and minimalistic apartment. Everything is clean. There are restaurants, convenience stores and a supermarket nearby. There is a refrigirator and freezer, but no utensils, since there is no kitchen.
It is a bit noisy around the clock, so bring ear plugs. This is probably the case in many other places too. I'm pretty sure this was listed as an "entire apartment" when I booked it, but now it's changed to "private room", which it actually is.
There is no desk in any of the rooms, even though the rooms are quite spacious for Japanese standards. In my room there were nothing but two beds and a very small TV on a small stand. I think the other room had a small sofa and hangers. It would be great to have desk where you can work with your laptop (I was there on business). And the small TV stand could be replaced with a small dresser, so you would have somewhere to put your stuff, if you need to empty your backpack.
The location is fairly good. Itabashikuyakushomae Station and Oyama Station are both about 6-7 minutes away. If you want to walk about 17 minutes to Itabashi station, you can take a direct train to Shinjuku or Shibuya.
The host was very helpful and didn't mind when I was unsure of my check-in time. He lives close-by and check-in is between 1 pm and 9 pm, which is very convenient.