That will depend on a few factors. The first is live in or live out?? Live in nannys tend to get less pay because room and board is considered part of thier earnings. Most live in's (and this is based on the DC area) that have been hired without the use of an agency make around $300 a week for full time. Live in's usually take on other chores besides child care..cooking, errands, laundry. If the children are in school and you don't plan to have the nanny do anything other than child care, you can offer less...about $150-$200 a week with the understanding she can take classes or get a part time job(make it clear your schedule takes priority over a job at the mall) in the time the children are at school or after you are home for the evening. If you are including a car and/or paying for better insurance on her car (key if she is expected to drive your children to dance, sports, car pool, etc) they are not considered part of her pay. A nanny from an agency will be higher..usually because you will be expected to provide health insurance through the agency as well as paying a fee to them. Agency nanny's tend to have stronger references, sound security checks and better training..so you can expect a minimum of $300 a week for them in a live in , child care only position, with the cost going up for extra responsibilities. Hiring an au paire (a nanny from another country, through an agency) will cost you less on a weekly salary, but more up front. You will pay the cost of transporting the person to the US and home again at the end of her contract (usually 12 months), as well as paying the cost of health insurance through the agency (a requirement for them to enter the country). Most agencys will limit the number of hours a week an au paire is allowed to work, but most girls are willing to work more for the extra cash. Using an agency can be a good thing becuase is there is a conflict of some sort, the girl doesn;t work out or other issues arise, you will be able to get a replacement much easier and usually will not have to pay the initial fees again.
Live out nannys are usually paid more of an hourly rate than a salary. The hourly may be a bit higher than a live in would work out to get, but they only work child care hours (unless your contract states otherwise) so get paid a bit less. I would expect to pay a live out nanny, working after school hours, about $200 a week. Again, this will change if you have children not yet in school, want her to take on some house keeping chores as well or will require her to work late evenings or overnights. A truely full time live out will usually get in the area of $350-$400 a week.
Former nanny, former nanny agent in DC