The panels on your roof matter, but the company that installs them matters more. A great panel installed badly can leak, underperform or fail an inspection. A solid installer will size your system honestly, handle the permits and stand behind the work for years.
This guide shows you how to check an installer's background, what warranties to ask for, and the sales tricks that should make you walk away.
What licenses and certifications should a solar installer have?
Start with the basics. A legitimate installer should be able to show you each of these without hesitation.
State contractor or electrical license
Most states require a contractor license, an electrical license, or both, to install solar. Some states have a specific solar license. Ask for the license number and look it up on your state's licensing board website. Check that it is active and has no serious complaints.
NABCEP certification
NABCEP, the North American Board of Certified Energy Practitioners, offers the most respected solar certification in the US. A NABCEP PV Installation Professional has passed an exam and has proven field experience. Not every crew member needs it, but a good company will have certified people designing or overseeing your job.
Insurance
Ask for proof of general liability insurance and workers' compensation. If a worker falls off your roof and the company has no workers' comp, you could face a claim. Liability insurance covers damage to your home. Ask for a certificate of insurance, not just a verbal yes.
What is the difference between workmanship, product and production warranties?
A solar system comes with several warranties. Each covers something different, and gaps between them can cost you.
| Warranty | Who provides it | What it covers | Good length |
|---|---|---|---|
| Workmanship | Installer | Installation errors, roof leaks from mounting, loose wiring | 10–25 years |
| Panel product | Panel maker | Defects in the panel itself | 12–25 years |
| Panel performance | Panel maker | Output staying above a set level, often 87%–92% at 25–30 years | 25–30 years |
| Inverter | Inverter maker | Inverter failure | 10–12 years (string), 25 years (micro) |
| Production guarantee | Installer or lease company | Pays you if the system makes less than promised | Varies |
The workmanship warranty is the one people most often forget. A panel maker will replace a faulty panel, but it will not pay to fix a roof leak caused by a bad mount. Only the installer covers that. Ask whether labor is included when a part is replaced under warranty. Some makers cover the part but not the cost of a crew to swap it.
A production guarantee sounds great, but read the fine print. Some only pay out if output falls far below the estimate, and some pay at a low rate per missing kWh.
How do you check an installer's track record?
- Years in business: Look for at least three to five years installing solar locally. Warranties are only as good as the company behind them.
- Local installs: Ask how many systems they have put in near you. Local crews know your utility and permit office.
- References: Ask for two or three past customers you can call. Ask them about the timeline, surprise costs and how problems were handled.
- Reviews and complaints: Read reviews on several sites, and check for complaints with your state attorney general or consumer protection office.
- Who does the work: Ask whether the company uses its own crews or hires subcontractors. Subcontractors are not always bad, but you should know who is on your roof.
What door-to-door and phone sales tactics should you watch for?
Solar has a large door-to-door sales industry. Many reps are paid by commission and may know little about solar. Watch for these tactics:
- Same-day pressure: "This price is only good today." Real prices do not vanish overnight. A fair quote will still be there next week.
- Tablet signatures: Being asked to sign on a tablet before you have a printed or emailed copy of the full contract.
- Utility impersonation: Reps who suggest they work with or for your utility, or say a "new program" requires you to act.
- Bill grabs: Asking for your utility account number or bill "just to check eligibility," then using it to start paperwork.
- Vague answers: No clear total price, no equipment brand, no answer about who installs.
Many states give you a short cooling-off period to cancel a contract signed at home. Ask about it, and get any cancellation in writing.
What is wrong with "free solar" pitches?
There is no such thing as free solar. When someone says "free," they usually mean one of these:
- A lease or power purchase agreement (PPA): You pay nothing up front, but you pay a monthly fee or a per-kWh rate for 20 to 25 years. The company owns the panels.
- A zero-down loan: You owe the full cost plus interest. Nothing is free.
- A "government program": Incentives can lower the cost, but they rarely make it zero. For what is available now, check current incentives in our incentives guide.
Also be wary of reps who promise a large tax credit. The US 30% homeowner tax credit (25D) ended for systems installed after December 31, 2025. Anyone still pitching it for a new home install is either out of date or misleading you.
How do installers inflate savings estimates?
A savings projection is only as honest as its assumptions. Look for these common tricks:
- High utility rate increases: Assuming your power price rises 5% to 6% every year. The long-term US average has been closer to 2% to 3%, per EIA data. Over 25 years, that gap can double the projected savings.
- No degradation: Ignoring the 0.25% to 0.5% yearly drop in panel output.
- Wrong export rate: Assuming 1:1 net metering when your utility uses net billing. See our net metering guide.
- Ignoring fixed fees: Claiming your bill will go to zero when you will still pay a monthly connection charge.
- Ignoring shade: Producing a production estimate without a real shade analysis.
Here is a quick check. Say a rep claims $60,000 in savings over 25 years on a $200 monthly bill. Your bill would total $200 × 12 × 25 = $60,000 at flat rates. So the claim assumes solar wipes out 100% of your bill, every year, with no fees. That is a red flag. Run your own numbers with our savings calculator.
Watch for lease escalators
Many leases and PPAs include an escalator, meaning your payment rises each year, often by 1% to 3.9%. It sounds small, but it adds up.
Take a $150 monthly lease payment with a 2.9% escalator. After 20 years, the payment becomes $150 × 1.02920, or about $150 × 1.77 = $265 a month. Your total paid over 20 years is about $48,000, compared with $36,000 at a flat rate.
If your utility rates rise more slowly than the escalator, you could end up paying more than you would have without solar. Leases can also complicate selling your home, since the buyer must take over the contract.
Installer checklist
| Check | What good looks like | Red flag |
|---|---|---|
| License | Active state license you verified online | No number, or "we use a partner's license" |
| Certification | NABCEP-certified staff on design or oversight | No certified staff |
| Insurance | Written certificate for liability and workers' comp | Verbal assurance only |
| Workmanship warranty | 10+ years, includes roof penetrations | Under 5 years or none |
| Quote | Itemized, with total price and $/W | Only a monthly payment |
| Savings estimate | 2%–3% rate rise, includes degradation | 5%+ rate rise, "bill goes to zero" |
| Sales process | Time to review, written contract | Today-only pricing, tablet signing |
| Permits | Installer handles permits and interconnection | Suggests skipping permits |
Once you have quotes in hand, use our quote checklist to compare them line by line, or request quotes to get started.
Frequently asked questions
How many solar quotes should I get?
Get at least three. Prices for the same size system often differ by 20% to 40%, and comparing quotes helps you spot inflated numbers.
Is a local installer better than a national one?
Not always, but local companies often know your permit office and utility well and may respond faster for service. Judge each on license, warranty and reviews.
What if my installer goes out of business?
The panel and inverter warranties still come from the makers, but you lose the workmanship warranty. This is why years in business and financial stability matter.
Should I pay the full price up front?
No. A common pattern is a small deposit at signing, a payment when equipment arrives or is installed, and the final payment after inspection and approval to operate.
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