This apartment is beautiful and in a beautiful, relatively quiet part of London, walkable to 2 parks for a morning walk. It is definitely fine for sleeping 4 people. The building is nice and safe.
I was disappointed that, after waiting post 3pm to check in, we had to request the extra bedding to be provided for the pull out bed, had to wait for extra towels, there was no hair drier nor paper towels etc for the kitchen, and we ran the dishwasher because utensils were dirty.