Mita Kaikan Hotel is a quiet, basic, clean, with full bath, WiFi and breakfast. Centrally located in Minato and close to Shiba Park and the Mita, Asakusa and Yamanote subway lines.
Although quiet, there are enough places to find a bite to eat or convenience stores like Lawson and Family Mart/Famima.
In terms of service and breakfast (choice of sandwiches or rice balls along with beverages and soups), it is basic but consider it's not typically included at most hotels and the staff is friendly. I was at the hotel for 4 days and it was a good stay as the price was about the same or less than a typical capsule hotel which has less privacy. I'd stay again.