Housing types and outdoor holiday decoration in Britain
I've got a xmas HP fic to write, and I'd like to set it in the Eastern part of Britain. Are there any things in particular that the East of Britain has regarding architecture? I'm thinking of having the main character living in what would be a duplex here in the States. A large house, built to be two residences, sharing either one wall or having one of the residences above the other. Would they be called flats? I want him to not live in an apartment building, but someplace where he's got control of/access to a small front garden and maybe a shared back yard. Is that possible? Does it exist?
Also, do people decorate the outside of their houses for the holidays in Britain? How much? I know that, here, some people/neighborhoods go beyond-the-pale; I'm not looking for the Truly Bizarre, but the average. Would there be just door wreaths or would there be lights as well?