It's normally taken at the end of the 2 year contract and she's entitled to 2 weeks. You are required to give her a one-way ticket home, but if you plan on renewing her contract then you would give her a round trip ticket.
Actually we have just signed the contract with this helper and she is waiting to get her new visa. She says she has already sent home the money which she got for her tkt to exit HK from her ex-employer. She wants to go home in April next year after she has saved the money for the trip. And for now she would just exit HK. We were aware of this situation before we signed the contract.
But that doesnt really suit us 'cos we will be expecting our baby then and would really need her to be around.
So in a nutshell, we are planning to send her off on her home leave right away. Dont think thats usually the practice, but we are hoping we like her and stick with her for the next 2 years!