Great homebase for exploring London with family. Myself, my husband, and my mother found Mark's flat to be perfect for our needs. Plenty spacious for 3, comfortable beds, great hang-out/cooking/eating space, the rooftop deck is fantastic, easy access to tons of restaurants and bars, quick walk to public transportation. Also, something that I always appreciate - Mark was very helpful and responsive to my messages! Last, I feel the need to mention that (1) this space is not at all cramped if you are aware of London standards - especially at this incredibly fair price - and (2) the stairs that people complain about aren't bad if you are in vaguely reasonable health (my 70 year old mother had no issues).
Bottom line, 100% would recommend to others!