20 Upper Baker Street is the home address of the Lorimer sisters, the protagonists of Romance of a Shop. Part of London's City of Westminster, Upper Baker Street was also the home of famous literary detective Sherlock Holmes. While it originated as an upper class residential neighborhood, commercial businesses moved in over time, which actually was indicated in Levy's work with the mention of a local chemist and photographer's studio (which would become extremely important to the plot).

"We have been looking at some rooms in Upper Baker Street," explained Gertrude, addressing her hostess; "there are two floors to be let unfurnished, above a chemist's shop."

"Two floors, and what else?" cried Conny; "you will never guess! Actually a photographer's studio built out from the house."

Mrs. Devonshire disapproved secretly of their scheme, and had only been won over to countenance it after days of persuasion.

"Some one has been failing in business there," she said, "or why should the studio stand empty?" (Levy, Ch. 4).