Yes, Au-pairs are typically paid 700-900 over here and yes you are right it IS UNDERPAID. I used to be an aupair a few years ago and I assure no matter what is included (rent, food, language course) this isn' t enough. It makes me cringe when I hear parents talking about how this is a perfectly fine wage.

These are your CHILDREN do you really wanna bargain on their care? You pay someone just enough and they'll do just enough but they will not be happy in Switzerland on that wage. Au pairs hangout with each other and moan about their jobs to each other. On that wage I ate never outside the house except the odd falafel which was a real treat. I was hardly able to leave Zurich and when I did it was on less then a "budget" travel.

For any parents looking to for a "good" aupair pay them well and they will treat your children well. Give them the bare minimum and that's all you can expect in return.