Very cozy old fashioned Japanese home! The extremely helpful host lives in the same building and rents all the apartments as airbnb. He was always nearby and ready to help when we needed him, but respected our privacy when we didn't. We forgot to get a converter for our European laptop recharger and he recommended a shop where we could find one. We ended up not having to go because a couple hours later he knocked on our door and handed us one!
It's undeniable that the apartment is quite old and has the creakiest floors I've ever experienced, but it's clean and equipped with all the modern amenities we needed. You need to use a separate heater for warm water, but it's pretty simple even if you don't understand Japanese. For our 8 night stay we were happy to eat out every night, but the small kitchen is well equipped if you actually want to cook for yourselves.
The location is at the western end of the Tokyo metro line a 5 minute walk and 10 minute ride from Shinjuku. Note that it's not connected to the JR train lines and you'll need to use the subway to get there, so I recommend getting a 24/48/72 hour metro card and avoiding the trains. This can seem like a challenge if you've been to Tokyo one or twice and only ever used the trains like I did, but is easy if you do some research or ask around a bit. For example Harajuku has no metro station and it looks like you need to switch to the Yamanote-line trains at Shinjuku, but the Meiji-jingu-mae metro station is actually very close.
The area of Hounan-chou is not one you've probably heard of before and there weren't many tourists or obvious non-locals around. It's great if you want to experience the non-touristy parts of Tokyo; shop and eat where the locals do. Probably not ideal of someone who's never been to Japan and doesn't speak any Japanese, but I loved it.