It depends on so many things:
On the books or off the books?
Is she supporting herself solely or "supplementing" a decent income
WHat does she need?
***
We pay (a lot) less than what the going rate is, but where we live Nanny is making _more_ than her mom - a pharmacy tech of multiple years.
Our accountant asked what we were paying and said "for babysitting?"
so it is not cut and dry.
Not all Nanny's are making 12-15 an hour. I think with the economy, some folks will work for considerably less because they would rather be with children and have a casual work environment rather than working at Taco Bell.
Our Nanny bust's her butt (mostly

) but she can also show up in flannel pj pants, do her laundry here, and take our kids out to run her errands - get her oil changed, take them back to her house to start dinner, check on her cats, run up to her college, etc. But at the same time - she is busting her butt taking my spectrum daughter to physical therapy and speech weekly as well as preschool and managing my little one at the same time. And dealing with me - no easy task!
You have to find the right person. You do get what you pay for. Yes, we pay less than typical, and our Nanny needs a lot of direction and we have quite a bit of frustration about getting day to day stuff done (her time management sucks) but she has been with us for well over a year and my kids adore her beyond belief.
Michelle