Twin Nanny/Mother's Helper Needed

I'm a new mom to 3-month-old twin girls, and I'm looking for someone who can help give me breaks or ease the load. My husband has a demanding job with a varied schedule, but it's set 2-3 months in advance, so we would be able to give you notice of times we'd need assistance well in advance. I know two babies at once is a bit crazy, and for the most part I will be available to step in and help if needed. So I would call what I'm looking for more of a mother's helper. Once we're comfortable with each other and you're comfortable with the babies it would be nice if I could step out for short periods to go to the gym or get my nails done or just have a few baby-free moments. I hope you don't mind cats, because we have three. Some light housework would also be included, mostly baby related tasks.