Solar panel installation represents a significant upfront investment, and the questions asked before signing a contract often matter more than the specific panel brand chosen. Start by asking for a detailed energy production estimate based on your specific roof orientation, shading, and local climate, rather than accepting a generic estimate that does not account for your property's particular conditions. Ask directly about the payback period — the time it takes for energy savings to cover the initial investment — and compare this figure across multiple providers, since estimates can vary significantly based on assumptions about future utility rates. Warranty coverage deserves close attention too, distinguishing between the panel manufacturer's warranty, the inverter warranty, and the installer's workmanship warranty, since these often have different terms and durations. Ask how the system performs during grid outages, since not all solar installations include battery backup capability by default, and this distinction matters significantly for households prioritising energy resilience. Finally, get references from customers whose systems have been installed for at least two to three years, since early performance data often looks better than the system's real long-term output.