Tokyu Stay Yotsuya was exactly the kind of hotel we were looking for. The hotel has a very central location, equally close to Shinjuku, Shibuya, Chiyoda and Minato districts. With JR rail lines and subway lines from the Yotsuya station you can easily get pretty much everywhere, for example with the yellow JB Chuo-Sobu line you can go to Akihabara or the main railway station in just 20 minutes.
I would say that the hotel is also a walking distance away Shinjuku, Chiyoda and Shibuya, around 3 to 5 kilometers. So you can take a nice stroll down to Shinjuku while doing some sightseeing.
The hotel rooms were spacious compared to many others in the same price range and had good basic amenities: electric kettle, microwave, fridge and even a washing machine.
Breakfast is served at the restaurant Jonathan where you have 8 different options, from continental to more traditional Japanese. We liked the food and we ate at Jonathan's even on few evenings.
What really saved our trip and made the whole stay so much more much more convenient was the Family Mart mini market downstairs. That place is a gem, with food, drinks, snacks, hygiene product, even cheap alcohol. you really don't need to to go out and eat if you'd don't want to. From family mart you get pretty much everything you need.
We recommend that you ask a room from the higher floor with the view to south. It was amazing!