How to Vet a Solar Installer

What should I check before calling any installer?

Start with your roof and your usage. The U.S. Department of Energy's Homeowner's Guide to Solar notes that panels work in all climates, but rooftops may be unsuitable because of age or tree cover, and that south-facing roofs with a slope between 15 and 40 degrees tend to perform best. Age matters too: if your roof needs replacement soon, that work should come first. Our guide to checking your roof before solar walks through that step.

You can also get a rough production estimate before any sales visit. The Department of Energy points to NREL's PVWatts tool for estimating energy production and cost for grid-connected systems at any address, and it cautions that such tools are only a starting point. A custom estimate from an installer is still needed. Walking into a first call with your own numbers changes the conversation from a pitch into a comparison.

Which certifications and credentials actually matter?

The Department of Energy names one credential directly: the industry-standard certification is awarded through the North American Board of Certified Energy Practitioners (NABCEP), and the best way to install solar is through a qualified professional who holds a certification and works with high-quality panels. That gives you a simple baseline. Ask whether the people who will be on your roof hold that certification, or whether the company subcontracts the work. The answer affects who is accountable if something goes wrong.

Credentials are not the only filter. The Department of Energy advises talking to certified installers and thoroughly reading reviews of solar companies, since you will likely have many options. Reviews are evidence, not proof, so read the negative ones for patterns: permitting delays, change orders, or trouble after commissioning.

How do I compare quotes fairly?

Quotes are hard to compare when they describe different systems. Ask every installer for the same outputs so you can line them up side by side. The Department of Energy notes that for its analyses NREL uses an average system size of 7.15 kilowatts direct-current with a 3 to 11 kilowatt range, which gives you a sense of typical scale, not a target for your home.

Beyond price, ask how the quote handles the pieces that often appear later. Here is a checklist you can run against each bid:

Item to compare	Why it matters
Estimated annual production	Compare like-for-like assumptions, not just system size
Roof condition and replacement timing	DOE guidance flags roof age as a suitability factor
Who performs the installation	NABCEP-certified staff or subcontracted crew
Financing structure	Purchase, loan, lease, or power purchase agreement
Battery storage option	Ask whether the installer offers storage
Net metering assumptions	Rules and credits depend on your state and utility
Incentive paperwork help	Local installers should assist with state and local incentives
Contract terms in writing	Review before signing anything

That last row is not a formality. The Department of Energy recommends carefully reviewing consumer education materials before signing anything with a solar company, including guides on buying panels, leases, power purchase agreements, and subscriptions.

What financing questions should I ask?

The Department of Energy states that a purchased system can generally be installed at a lower total cost than one financed with a loan, lease, or power purchase agreement. If you prefer to buy, solar loans can lower upfront costs, and some jurisdictions offer subsidized loans with below-market rates. Leases and PPAs let you host a system owned by a solar company and buy the electricity, often with no money down, but you do not receive tax benefits because you do not own the system.

That single ownership distinction reshapes the deal. Ask each installer to show the same scenario in the same format, and ask who claims the tax credit. Our comparison of ways to pay for home solar lays out the tradeoffs. This is general information, not financial advice; confirm current federal and Indiana rules with the IRS or a tax professional before relying on any credit figure.

How does net metering affect the comparison?

The Department of Energy explains net metering as an arrangement in which system owners are compensated for solar power exported to the grid, and it cautions that the practice is rarely as simple as a meter running backward since the 1990s. Whether your system qualifies depends on policies and practices in your state and electric utility, and the department suggests your local utility as a good source for information, with basic questions about availability, eligible system size and customer type, rates, and bill credit design.

In Indiana, those answers vary by utility territory, so two neighbors can face different economics. Ask each installer what they assume about your utility's net metering treatment, and whether the assumption is documented. Our explainer on what net metering means for a home and our piece on how utility territory shapes solar access go deeper. If you want to understand the policy layer behind the numbers, our primer on how Indiana energy policy reaches solar is a useful starting point.

What are the warning signs of a bad deal?

The Department of Energy acknowledges that most people going solar have a positive experience, but that rapid growth has opened the door to a small subset of bad actors. Its Smart Shopping Tips for Solar lists red flags including pushy sales tactics. In August 2024, the Treasury Department, the Consumer Financial Protection Bureau, and the Federal Trade Commission issued a consumer advisory to help consumers identify potential solar scams and file complaints.

If a company misrepresents itself or its products, the Department of Energy points to several channels: ReportFraud.FTC.gov for the FTC, a complaint with the CFPB online or at 1-855-411-CFPB, state consumer protection offices through usa.gov/state-consumer, your state's utility consumer advocate through nasuca.org/members, and nonprofit legal aid through lsc.gov or lawhelp.org. The Better Business Bureau at bbb.org is another place to check complaint history before you sign. This is not legal advice; for a dispute, consult a qualified attorney or the agencies above.

Which contract clauses deserve a second read?

The Department of Energy's guidance is direct: before you sign any documentation with a solar company, carefully review the educational materials it links, covering purchases, leases, power purchase agreements, and subscriptions. Practical items to look for in the contract include the financing structure, who owns the system and claims incentives, production estimates and their assumptions, and how the agreement transfers if you sell the house.

Resale is a real consideration. The Department of Energy cites a study finding buyers paid a premium of about $15,000 for a home with an average-sized solar array, and notes evidence that homes with solar sell faster. For third-party owned systems, data shows added complexity in the transaction, though overall impacts on sale price, time on market, agreement transfers, and customer satisfaction are mostly neutral, and in some cases such systems can add value. Ask how the contract handles a sale before you sign it. Our notes on clauses to notice in a solar contract cover this ground.

What else should I ask before deciding?

Two more questions worth raising. First, storage: the Department of Energy notes that adding energy storage lets you use solar power when it is needed most, day or night or during an outage, so ask whether the installer offers battery options. Second, your HOA: in most cases you can install solar even under an HOA, though you will likely submit a request, and many states have solar access laws preventing HOAs from prohibiting or unreasonably restricting installations. Those laws vary by state, so confirm what applies in Indiana.

Finally, keep the process in perspective. Community solar remains an option if your roof is unsuitable or you do not own your home, because a shared array divides costs among participants. Our community solar basics for Indiana explain how that works. Whether you buy or subscribe, the same discipline applies: same questions, same format, written answers, and time to read before signing.