My friend and I stayed in Jay's apartment for 6 days, and it was very convenient to go back to it every night after exploring Tokyo. There are many restaurants and shops located around the apartment, and it is very easy to find on the street.
If you are a large framed person (my friend powerlifts and has a very muscular frame with a height of 5 feet 6 inches), meaning larger than the average sized petite Japanese citizen, then you might have problems using the bathroom. The space is very small in there, and my friend bumped her knees and hands against the walls multiple times when using the toilet. The bathroom is very tiny. Sufficient for me to use, but was of some difficulty for my friend.
Jay provides umbrellas and reliable pocket wifi. That was SO INCREDIBLY helpful, especially since we had a day full of dreariness and rain during the trip.