Search for local installers who are licensed for the plumbing and electrical work your system requires, and check their experience with solar hot water and heat-pump systems. Ask for itemised quotes covering the unit, installation, upgrades, warranties, approvals and removal of the old system, rather than comparing equipment prices alone. You can also check whether the installer is accredited for any rebate or certificate scheme that may apply in your state. Eligibility and available incentives depend on your circumstances, so confirm details with the installer and the relevant government website before signing.