Get at least two or three itemised quotes and check what is included, such as panels, inverter, scaffolding, installation, monitoring and grid connection. Confirm the installer is appropriately licensed in your state and uses an accredited professional where required for government incentives and grid-connected work. Check recent reviews, product and workmanship warranties, insurance, and whether the business has a clear complaints process. Before signing, compare the system design and expected performance, and ask the installer or your electricity distributor about approval requirements.