There's no point looking for a mansion if you can only afford a unit. Once you've set your price range, its time to identify the suburbs that you prefer and to search in that range - it will save you a lot of legwork.
Now comes the fun part: finding the house or unit you want. Take your time consider things like proximity to schools, transport and amenities, and the condition of the property.
Always make sure if you have people helping with inspections, that they are qualified to do so, that they are a licensed builder, architect or surveyor.
If you plan to buy a property as an investment, rather than as a home to live in, then read this information about investing in property.