My stay in Tokyo was great. Tokyo portraits a very interesting culture and incredible infrastructure thus there is nothing like the japanese etiquette. Yukiko's place is located in a quiet and residential place. Not touristic so very good to relax at the end of the day and experience life near locals, yet there are many service providers nearby such as 24h convenient stores, different kinds of japanese restaurants, shops, health care etc. It feels like a very cozy neighbourhood. Senju is like "downtown Tokyo" however, but accessible to the most populous areas of the city by metro (the nearest metro station is 8min walk and there you find 2 metro lines and a JR line), very convenient.
Yukiko quickly answered any questions regarding the accomodation and the local area and was waiting for me at the train station upon my arrival, before the chek-out she gave me precise information of how to reach the airport (very easy BTW). As long as you stick to Yukiko's house rules your stay in this place can be very good. Defintely recommended.