Ohkubo was a great host. We got in before the check in time and didn't want to haul our luggage so he invited us to drop it off at the house. He happened to be there when we dropped it off and we asked him where a good spot was to grab some food. He told us about a great place, walked us there, then helped us order (we don't speak Japanese).
The apartment was nice, clean, and cozy. The location is great, walkable to everything, but out of the hustle and bustle. Very quiet, very safe.
The pocket wifi was the life saver that we didn't know we needed. There would have been NO WAY of us being able to navigate Tokyo without it.
NOTE: for those traveling, the very specific and helpful directions to the apartment from the train station are from Okubo station, ShinOkubo station is different although it is just a few blocks from Okubo station, we made that mistake and were a little lost right away.