Check that the installer holds the relevant state or territory electrical licences and, where applicable, current Clean Energy Council accreditation. Get at least two or three detailed quotes covering system size, panels, inverter, installation work, warranties, monitoring and any extra costs. Ask who will perform the electrical work, how grid connection will be managed, and whether the proposed system suits your roof, energy use and switchboard. Before signing, read the contract carefully and verify product warranties with the manufacturers; an independent electrician can also help assess technical advice.