Hi Msblur/Emma,
I installed the cameras during my renovation. So I have most of the wires hidden.
Actually if they want to do something, they will definitely think of ways to do it, regardless of whether there is someone at home or not. Remember the case whereby the baby was thrown out of the window when the grandma was taking her nap?
I just close one eye on housework and always emphasize that the focus is on DS. Whenever I travel, I'll definitely get something for my maid. When I have extras from my HK LD, I'll give her one too. All these really make her days.