The flat is in a 6th floor, but the building has lifts, so no need to get tired going upstairs. I slept very well, no noise from the neighbors or due to a busy street.
The place was absolutely clean and it had everything I needed for my stay, even a desk. The bed was also very comfortable.
Tube stations are at a walking distance from the flat and the area looks safe for walking at any time.
Maria was very nice and helpful. The night I arrived I struggled finding the place, due to lack of internet access and bad organization of my trip (not the smartest thing I've done), but Maria was quite patient and in the end, once I was in the neighborhood, she went to pick me up.
The next day she even lent me her Oyster card.