Describe symbolism in The Line of Beauty by Alan Hollinghurst

Kensington Park Gardens is surrounded by communal gardens where residents must have a key to enter. The key is a symbol of belonging in this exclusive neighborhood. There are some cottage homes in the neighborhood, which are not as grand. Nick's bedroom is up in the roof, in the children's area. The fact that his bedroom is located at the farthest end of the home also symbolizes that although Nick lives in the Feddens' home, he is not a central member of the family.