Booked this flat for my parents during their stay in London. The flat is nice in general, conveniently located close to several underground stations, many tourist attractions, restaurants, supermarkets. There is a bus stop just moments away from the flat. Kensington gardens and Portobello road are within walking distance (less than 10 min).
The flat is on the 2d floor with no lift. For us it was not a problem, it's London and there are plenty of Victorian buildings like that.
The flat is equipped with everything you need in case if you want to cook. The washing machine is at your disposal.
However, we had some serious cleanliness issues, and I basically moped the floor and changed the bedlinen by myself.