E.M.
Well, sitter city has a calulator on its site that tells you is standard.
I am always looking for someone to babysit for about 3 hours a week (doctor appointments, date night, getting x-mas presents...) so I get that you are just babysitting and not looking for a full time thing.
I know that, at least in my area, people are alwaysnlooking for overnight sitters, so if you are up to that you M. well make a killing.