10 questions to ask a solar installer

Quotes are easier to compare when you ask everyone the same things. Bring this list to any consultation.

What's the net price per watt, after incentives?
What equipment (panel and inverter make/model) are you proposing, and why?
What system size (kW) and estimated annual production (kWh) — and how did you calculate it?
What are the warranties — product, performance/degradation, and workmanship — and who honors them?
Am I buying, financing, or leasing? If financing, what's the rate and any dealer fee baked into the price?
Who claims the tax credit — me or you? (With a lease/PPA, it's them.)
How does net metering work with my utility, and how did you model it?
Are you using your own crews or subcontractors, and are you licensed and insured here?
What happens if a panel or the inverter fails in year 8? Who do I call?
What's not included — roof work, electrical upgrades, permits, monitoring?

Tip: get at least two or three quotes and compare the net price per watt and the warranties — not just the monthly payment.