The amount you can earn whilst tutoring from home varies depending on where you live (the socio-economic demographic), the population density, the competition and your level and experience. If you are just starting out as a tutor or teacher you will need to do some research into how much people are charging near you for similar services. Start by looking online or in the local paper to get a feel for standard rates. Remember not to base your rates on just one or two other people as they may well be over-charging and not getting any business themselves!
Once you have set your rates, don't be afraid to charge extra for things like travel or other out-of-pocket expenses. Many tutors will even lower their rates for long-term bookings or for people who are economically disadvantaged.
Like any business, don't expect to be over-run with clients in the short term. Building up trust and reputation takes a long time. Keep yourself motivated by learning new teaching techniques and researching your subject thoroughly. The better the reputation you build the more you will be able to charge per hour.
Tutors in Sydney can earn anything from $30 to $110 an hour. The tutors that charge towards the lower end tend to get a lot more inquiries than the top end, but then they also have to do about four times the amount of work to earn the same money! It all comes down to how much time you want to spend tutoring (experience at first is best) vs how much you want to earn that is realistic.