Has anyone got their house wired who leaves their baby with a nanny alone?? Does it really help?

It is good to install a cctv at home to monitor your nanny and baby. Also, make sure that you install a few areas in the house that can see nanny handling your kid, e.g. living room, baby's sleeping room, kitchen and etc. You should inform your nanny about the installation of the cctv and explain the purpose of the installation so to avoid misunderstanding between you and nanny, e.g. you are not trusting her.