Your solar system will be on your roof for 25–30 years. The company that installs it needs to be around for the warranty claims, monitoring, and panel upgrades that come with that lifespan. Unfortunately, solar is one of the industries with the highest churn of small installers — so vetting matters. Here are the ten questions we recommend asking every candidate before you sign anything.
1. Are you licensed and insured in my state — and can I see the numbers?
Ask for their state electrical or home-improvement contractor license number, plus a certificate of insurance showing at least $1 million general liability and active workers' compensation coverage. Then verify both. Licensing boards publish status online for free; insurance certificates can be verified by calling the listed broker. Unlicensed or lapsed installers should be disqualified immediately.
2. Are your installers NABCEP-certified?
The North American Board of Certified Energy Practitioners is the solar industry's gold-standard credential. Ask specifically whether a NABCEP PV Installation Professional or PV Design Specialist is on-site during your install — not just listed on the website. A company with zero NABCEP staff is a yellow flag in 2026.
3. How long have you been in business, and how many installs have you completed?
Five years in business and 500+ completed installs is a reasonable threshold in 2026. Ask for exact numbers, not marketing language. Newer companies can absolutely do great work — but if they go bust, your workmanship warranty goes with them. Cross-reference with the Better Business Bureau, Google reviews, and our verified directory.
4. What panels and inverters do you install, and why those?
A good installer has 2–4 panel options and 1–2 inverter options. Beware of installers who only offer one brand at every price point — they're often selling you whatever they have in a warehouse, not what fits your roof. Ask:
- Are the panels tier-1 (Maxeon, Silfab, Qcells, REC, Canadian Solar)?
- Are the inverters Enphase (microinverters), SolarEdge (DC optimizers), or a reputable string inverter like SMA or Fronius?
- What is the production warranty? (25 years at 88%+ is the modern standard.)
5. What workmanship warranty do you offer?
Panels have 25-year warranties from the manufacturer. Inverters have 10–25 year warranties. But the physical labor — mounting, flashing, wiring — is only as good as the installer's workmanship warranty. Insist on 10 years minimum; 25 years is best. Make sure it covers roof penetrations (leaks) and is transferable if you sell the home.
6. Can you give me three references from installs completed in the last 12 months?
Recent references are far more useful than older ones because equipment, crews, and financing terms change. Call at least two. Ask:
- Did the project stay on the quoted budget and timeline?
- Was the crew professional and tidy?
- Any leaks, production issues, or monitoring problems in the first year?
- How is post-install service — do they answer when you call?
7. Who handles permitting, interconnection, and incentive paperwork?
A quality installer handles all of it — building permit, electrical permit, utility interconnection application, NYSERDA/NJBPU/state rebate paperwork, SREC registration, and net-metering enrollment. If an installer wants you to file any of that yourself, that's a red flag.
8. Will the system be designed with shade analysis and production modeling?
Ask to see a site-specific shade analysis using PVSyst, Aurora, or HelioScope — not just a generic Google Earth sketch. You should receive a year-1 production estimate in kWh and a 25-year production forecast. If an installer won't commit to a production number, they probably won't stand behind the system either.
9. How is the system monitored, and what happens if production drops?
Modern systems include panel-level monitoring via an app (Enphase Enlighten, SolarEdge mySolarEdge, SMA Sunny Portal). Ask:
- Will I have access to real-time production data?
- Who monitors it on your side, and how fast do you respond to alerts?
- What is your service-call pricing after the workmanship warranty expires?
10. Can you provide a fully itemized, written quote?
A professional quote shows: system size (kW DC and kW AC), panel make + model + quantity, inverter make + model, battery make + model (if included), racking, permit & interconnection fees, engineering, labor, warranty summary, and the final gross and net-of-incentive price. Quotes with a single "bottom line" number and no line items are designed to hide equipment substitutions and margin — walk away.
Bonus: three things a good installer will do without being asked
- Offer a critter guard (mesh perimeter around the array) to keep squirrels, pigeons, and rats out of the wiring.
- Install snow guards on appropriate roof types where snow-shed can damage gutters or landscaping.
- Proactively explain what happens if you sell the home — system transfer paperwork, net-metering agreement continuity, and warranty reassignment.
Red flags to watch for
- High-pressure "tonight only" pricing or door-to-door scripts
- Installers who won't let you speak to past customers
- Lease or PPA contracts with annual escalators above 2.9%
- Quotes that won't itemize equipment makes and models
- Promises of "free solar" — it's always financed, somehow, by someone
Running candidates through these ten questions takes about 45 minutes per installer and will save you years of regret. When you're ready, our Get Matched form sends your project to up to five vetted contractors who already meet these standards — at no cost.
Frequently asked questions
What should I look for when hiring a solar contractor?
Look for an active state license, $1M+ liability insurance, NABCEP certification on the install crew, at least 5 years in business, tier-1 panel options, a 10+ year workmanship warranty, recent references, and an itemized written quote. Avoid anyone who pressures you to sign immediately or refuses to share equipment details.
How do I verify a solar installer’s credentials?
Verify the state contractor license on your state licensing board’s website, call the insurance broker on their COI to confirm active coverage, check the NABCEP certification lookup at nabcep.org, and cross-reference reviews on Top Solar Services, Google, and the BBB.
What workmanship warranty should a solar installer offer?
Ten years minimum, with 25 years being best-in-class. The warranty should cover roof penetrations (leaks), electrical workmanship, and monitoring setup, and should be transferable if you sell the home.
Is it safe to choose a newer solar company?
It can be, but understand the risk: if the company closes, your workmanship warranty goes with them. Make sure the panels and inverters have strong manufacturer warranties that are enforceable independently of the installer, and strongly prefer companies that are at least 5 years old.
Should I get multiple solar quotes?
Yes — three quotes is the sweet spot. It is the single most effective step for getting a fair price, and it surfaces quality differences in system design and equipment selection. Our Get Matched tool delivers up to five quotes from vetted contractors in under 24 hours.
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