After moving to a new city, an electronics professor had problems finding a place to live, so he chose the option of sharing a house. The place had a good environment-until some flatmates obtained new jobs. After that, more people were arriving at the house looking for a specific inhabitant. However, with a single bell on the door, it was difficult to know whom each guest was seeking. By taking advantage of electronics modules, an easy, low-cost integration was developed. The solution mainly used an MP3 circuit and a power audio amplifier, among other electronic elements. To differentiate each person in the home, real bell sounds were collected and recorded. The integration makes it easy to know with whom a visitor is arriving to meet. This solution was also used by an elevator company.