Guide
Is my Arizona solar quote fair? Read it in cost per watt
Updated
Two quotes for the same house can look nothing alike until you divide each total by the system's watts. Then they are directly comparable, and the differences become questions you can ask.
The one calculation that makes quotes comparable
Take the total installed price, before any credit, and divide it by the system size in watts. A 7.6 kW system is 7,600 watts, so a $23,000 quote is $3.03 a watt. Do it for every quote you hold. Our calculator does the same arithmetic in reverse: it takes a size and a price per watt and gives you the total, plus the Arizona credit and the net figure.
Compare like with like. A cash price, a price with dealer financing built in, and a lease payment stream are three different things. Ask every installer for the cash price of the same system, then compare those.
What should be inside the price
- Panels, inverters or microinverters, racking and all mounting hardware.
- Electrical work, conduit, disconnects, monitoring, and any main service panel upgrade the design requires.
- Permits, plan review, city and utility inspection fees, and the interconnection application.
- Roof penetrations and flashing, plus a workmanship warranty in writing that names who honors it.
- Removal and reinstallation terms if the roof is replaced later, which is a real Arizona cost given roof lifespans in the heat.
Lines that quietly move the number
- Financing fees rolled into the price
- A low advertised interest rate is often paid for with a dealer fee added to the system price. Ask what the cash price would be, and compare the two totals rather than the two monthly payments.
- A federal credit shown as a discount
- The IRS states the residential clean energy credit is not available for property placed in service after December 31, 2025 (irs.gov). A quote that nets a 30% federal credit off the headline price in 2026 needs a written explanation. See our credit guide.
- The Arizona credit shown as a price cut
- The state credit reduces Arizona income tax you owe, up to $1,000. It is not money the installer discounts, and it is worth less to a household with a small state tax bill.
- Production estimates you cannot check
- Ask for the modeled annual kilowatt-hours, the tool that produced them, and the assumed shading. Then ask what happens if actual production falls short: many warranties promise nothing on output.
- Sales tax on solar equipment
- Arizona lets a registered solar energy retailer deduct sales of solar energy devices from the transaction privilege tax base (ARS 42-5061(M)). Ask where that shows on your quote.
Before you sign
- Get at least three cash prices for a comparable design, and convert each to cost per watt.
- Check the contractor's license with the Arizona Registrar of Contractors, and confirm who actually performs the work if the salesperson works for a different company.
- Read the cancellation terms and any lien, escalator or transfer clauses. A twenty-year agreement attached to your house deserves an hour of your time.
- Ask your utility which export rate and rate plan will apply, using our export rate guide as the checklist.
Cost per watt is a comparison tool, not a verdict. A higher price per watt can be right if it buys a better roof detail, a needed panel upgrade or a warranty that someone will honor.