The office of a doctor, artist, lawyer, dentist, architect or a professional engineer, when not located outside of the building in which he resides, provided that there is no display other than the ordinary professional nameplate not larger than eight inches by 15 inches, and provided that, where the plot is an interior plot, the entrance to such office shall be approximately at the front building setback line and, where the plot is a corner plot, the entrance shall be approximately at the building setback line of either street frontage, and provided, always, that such use shall not be so conducted as to be an annoyance or nuisance to the neighborhood.