I Fired my bun last week. You should take care of her taking or stolen your private things such as ID copy & the tax receipt. Don't leave your kids in the house & you should need to accompany with her to downstairs. Prepare the documents & the money & need to sign. Don't let your maid know & don't give her any sign you want to fire her.(唔聲唔聲, 佢志知驚)
BTW, I'm so afraid the new bun as most of them is not the first time to come to HK. (just change her name in philippines). :-(