House sitting or house swapping forum?

My husband, myself and my kids are new to Hong Kong from the US. We are teaching at an International School. This year, the school provides an apartment, but we are already looking ahead to the next school year. I was wondering if there is any market at all for house-sitting in Hong Kong? Any forum that anyone knows of? Ideally, we would love to house/pet sit long term...maybe for someone who travels extensively or who is going on a year sabbatical but who doesn't want to give up their home/apartment. We would even be willing to do a house swap for our home in rural Maine for someone who is looking to get away from the rat race. Is this ever done over here? Obviously, we are wanting to avoid the high rent, but we would also be a cheap (free!!) alternative to hiring a helper to watch your house. Google searches have left me wondering if this exists in HK...

We are thinking more along the lines of actually caring for pets/gardens/mail, etc. This is something that is in higher demand in other countries, not because we are worried about our homes being safe, but rather to have someone to look after the things I listed. I realize housing is at a premium here, and most people don't have grounds or pets, but I figured it was worth a query. Why would someone do this if they could sublet? Well, I can't answer for everyone, but we let a family we didn't know use our home for a whole year for the cost of utilities only. Why? We had to be in another city for that time and it seemed like a nice thing to do. (No, we aren't wealthy) So, you never know unless you ask! And yes, we can afford to pay, which I'm sure we will end up doing. Thanks for your thoughts.