I got a policy from QBE (tel 2877 8488) which was recommended by my helper. The premium is more than the others mentioned ($1350 per year) but they refund $150 per doctor's visit. I looked into the HSBC one that's an addition to the home insurance and it was very cheap but a joke, the very rare events that they would actually cover. Don't forget that you have to meet your helper's medical expenses that are not covered by insurance, so it might be worth paying a little more to get some of those covered.