Questions to ask
1. Are you licensed as a contractor (and electrically licensed where required), and can you show general liability insurance and workers’ compensation?
Why it matters: Solar work combines roofing risk with electrical interconnection. Many jurisdictions require a contractor license and a licensed electrician for DC/AC work and the utility tie-in. Ask for license numbers you can verify with your state or local board, a certificate of insurance naming your address for the job dates, liability limits, and workers’ comp if they have employees. Uninsured falls, fire, or property damage become your problem. “We’re bonded” is not the same as liability coverage — get carrier name, policy number, and dates in writing before work starts.
2. Who on the team holds NABCEP (or equivalent) credentials, and what is their role on my project?
Why it matters: NABCEP certification is a widely recognized industry credential for PV installers and designers; it is not a substitute for a legal license, and not every good installer has it. Ask who is certified (designer vs installer), whether that person will design or supervise your job, and how design reviews and inspections are handled. Treat “NABCEP company” marketing carefully — ask for the individual’s name and credential type. Credentials plus verified licenses beat logos alone.
3. What does your site survey include — shade analysis, roof measurements, electrical service review — and how do you build the production estimate?
Why it matters: Production estimates drive system size, financing, and bill expectations. Ask whether they use on-site shade tools or aerial data, how they account for orientation, tilt, nearby trees, and seasonal shading, and which software or method produces the kilowatt-hour estimate. Request the assumptions in writing (system size in kW, estimated annual production, derate factors). Vague “you’ll cut your bill in half” without a documented methodology is a red flag. Do not treat any estimate as a guarantee unless a written production guarantee says so.
4. Which panel, inverter, and racking brands will you install, and what warranties cover product, workmanship, and production?
Why it matters: Equipment and warranties vary widely. Ask for exact models (panels, string or microinverters / optimizers, racking), manufacturer product warranty length, and whether there is a separate performance/production warranty. Clarify the installer’s workmanship warranty (roof penetrations, leaks, mounting) and who you call if a panel or inverter fails — manufacturer, installer, or a third-party warranty admin. Get serial-number and registration responsibilities in writing. Lifetime marketing language with fine print that voids for “any roof work” is weak protection.
5. What is the condition of my roof, who assesses structure, and who repairs or replaces the roof if needed — before or after panels?
Why it matters: Panels last decades; a roof near end-of-life may need replacement first. Ask who inspects decking and structure, whether a roofer is involved, and whether roof work is included, excluded, or quoted separately. Confirm who warrants leak repairs around penetrations and what happens if the roof must be replaced later (panel removal and reinstall cost). Door-to-door quotes that ignore roof age often shift expensive surprises to you mid-project.
6. Who pulls building permits, handles utility interconnection and approval, and owns those fees in the contract?
Why it matters: Solar usually needs building/electrical permits and utility permission to interconnect. Ask who submits applications, who pays AHJ and utility fees, typical timeline to permission to operate (PTO), and what happens if the utility requires upgrades (panel, meter, transformers). Get permit and interconnection as clear line items or exclusions. Crews that start install before permits or leave you to chase the utility alone create delay and liability risk.
7. How will this affect my utility bill under net metering or successor tariffs — and what assumptions are in your bill-savings pitch?
Why it matters: Net metering, export credits, and time-of-use rates vary by utility and change over time. Ask which tariff they modeled, whether they assumed full retail credit for exports, how non-bypassable charges or fixed fees are treated, and what happens if rate structures change. Insist on a written explanation of assumptions — not a round “savings” number with no basis. No installer can honestly lock future utility rates; treat bill impact as an estimate, not a promise.
8. Is this a cash purchase, loan, lease, or power purchase agreement (PPA) — and who owns the system and the tax incentives?
Why it matters: Ownership drives who gets federal/state incentives (where available), who claims depreciation or credits, and who is responsible for maintenance and insurance. Ask for a clear contract type, APR or lease/PPA escalation terms if financed, whether you or the finance partner owns the equipment, and how buyout or transfer works if you sell the home. High-pressure “sign today to lock the rebate” without time to read loan or lease documents is a classic red flag. Compare cash and financed options with the same equipment scope before choosing.
9. What is the install timeline, what triggers change orders, and what monitoring system will I get after permission to operate?
Why it matters: Weather, permit queues, equipment lead times, and utility backlogs stretch schedules. Ask for a written sequence (survey → design → permits → install → inspection → interconnection → PTO), how change orders are priced if roof or electrical upgrades appear, and which monitoring app or portal shows production. Confirm you receive login access and who troubleshoots underperformance after handoff. Open-ended schedules with no written milestones make it hard to hold anyone accountable.
10. What happens if actual production underperforms the estimate, and how is payment structured across milestones?
Why it matters: Some contracts include a production guarantee; many do not. Ask whether underperformance triggers a refund, system adders, or nothing — and get that in writing. For payment, prefer milestones tied to design approval, material delivery, substantial completion, and final PTO or inspection — not a huge cash-only deposit before permits. Large upfront cash demands, no itemized scope, or “pay in full today for a discount” without a detailed contract are warning signs.
11. Can you provide recent local references for similar roof types and system sizes, and will I get a complete written scope before signing?
Why it matters: References from homes with comparable roof pitch, age, and system size beat generic star ratings. Ask for two recent local customers, how long the company has operated in your area, and a written scope listing equipment models, kW size, estimated production method, roof/electrical exclusions, warranties, permit/interconnection responsibility, payment schedule, and monitoring. Door-to-door only quotes with no office trail or written proposal are harder to verify and enforce.
Red flags
- High-pressure same-day sign — especially tied only to “rebate expires tonight” without leaving a detailed written quote.
- Vague production or bill-savings promises with no site survey method, assumptions, or written estimate.
- No written scope: missing equipment models, warranties, exclusions, or who owns permits and interconnection.
- Roof work excluded or ignored without disclosing roof condition, leak warranty, or reinstall costs later.
- Door-to-door only quotes with no verifiable license, insurance certificate, or local references.
- Unclear loan vs lease vs PPA ownership — or pressure to skip reading finance documents.
- Large cash-only deposit before permits or work, no receipt, no milestone schedule.
Next-step checklist
- Verify contractor and electrical licenses locally; get liability (and workers’ comp) certificates naming your address.
- Ask about NABCEP or equivalent credentials by person and role — and confirm licenses separately.
- Compare at least two written proposals with the same equipment scope, survey method, and ownership structure (cash vs finance).
- Confirm roof assessment, who repairs leaks, and whether roof replacement should happen before panels.
- Clarify who pulls permits, who handles utility interconnection, and what fees are included.
- Read loan, lease, or PPA terms for ownership, escalation, buyout, and incentive claims before signing.
- Hold final payment until inspection/PTO milestones in the contract are met and you have monitoring access.