i used to be an on call babysitter in brisbane for a couple of hotels. i would just go there. have a chat with the parents, get to know the kids.
we were there to look after the kids, not watch tv.
they get good agencies to do this.. i wouldn't be concerned with the quality of babysitter. just explain to however it is what you expect them to do... if you want them to sit in the room with your child then tell them that.