Hiring cleaning help

So I'm hiring a local SAHM to help me with some cleaning/organizing. She's self-employed (found her on Craigslist). Do I tip her, or just pay her the hourly rate she charges?

Am I crazy for wanting to pull an all-nighter trying to declutter/organize before the cleaning lady comes over tomorrow so she doesn't think I'm a slob? :(

Have you ever hired cleaning help? How did it go?