For the equipment of the house, we chose the Bellman Visit 868 systems:

The Bellman Visit 868 system is a wireless alert system. It consists of at least one transmitter and one receiver. The transmitter hears the alert: a phone ringing, a baby crying or the outbreak of a fire. The receiver warns you of warning by flash or vibration. It is able to differentiate the different emitters and you signal using color diodes which triggered.

An example: When the doorbell rings, the transmitter signals the pager on your belt. The pager’s gentle vibrations will tell you that your guests have arrived; or, when the phone rings, the transmitter signals the Flash in your living room. The bright lights will show you that someone is trying to get a hold of you.