The cost of solar panel installation in Brisbane can vary depending on several factors, such as the size of the solar system, the type of solar panels used, and the complexity of the installation. However, the average cost of installing a 6kW solar panel system in Brisbane can range from $4,000 to $10,000. It is important to note that this cost may be reduced with government incentives and rebates, which can significantly lower the overall cost of solar panel installation Brisbane. Additionally, it is recommended to obtain quotes from multiple reputable solar companies to ensure that you are getting the best price for your solar panel installation Brisbane.