Use a solar installer checklist to confirm the business is properly accredited, insured and experienced with systems like yours. Compare written quotes covering panel and inverter brands, system size, installation work, warranties, monitoring, grid connection, approvals and any Small-scale Technology Certificate (STC) discount. Check the contract carefully for payment terms, timelines, roof access, workmanship guarantees and what happens if an item is unavailable. You can also look for independent reviews and ask for recent customer references, then confirm technical and electrical requirements with the installer or a licensed electrician.