There are a lot of factors that go into the cost of building a pergola in Australia, such as the size and complexity of the project, the materials you choose, and the contractor you hire. But on average, you can expect to pay around $3,000-$4,000 for a basic pergola.
If you're looking for something more elaborate or custom-made, the cost will obviously be higher. And if you need to remove an existing structure or do some major landscaping work before building the pergola, that will add to the overall cost as well.
But with a little bit of research and planning, you can definitely find a pergola that fits your budget