Questions to Ask Before You Choose a Solar Installer

How long have you been installing solar in Minnesota specifically?

Experience in Minnesota specifically matters — not just general industry experience. An installer with a decade of Minnesota work has navigated local permitting processes, built relationships with Xcel Energy’s interconnection team, and understands installation conditions specific to this climate. Ask for a number of years in Minnesota, not a vague claim about experience.

How many residential systems have you installed in Minnesota?

Volume indicates operational maturity. A company that has installed 500 residential systems in Minnesota has encountered and resolved problems that a company with 50 installs has not yet faced. Ask for a specific number. A vague answer — “thousands” without documentation, or a redirect to national numbers — warrants follow-up.

Are you licensed and insured in Minnesota?

Minnesota requires electrical contractors to be licensed through the Department of Labor and Industry. Ask for the license number and verify it through the Minnesota DLI contractor lookup tool — free and available online. This is standard due diligence, not an accusation, and any reputable installer provides the information without hesitation.

General liability and workers’ compensation insurance protect the homeowner if something goes wrong during installation. Ask for certificates of insurance, not just a verbal confirmation. An installer who cannot produce insurance documentation on request is not ready to work on your property.

What is your company structure — locally owned, regional, or national?

This is not a question with a right answer. What the homeowner is actually evaluating is stability: if this company faces financial difficulty in five years, what happens to the warranty? A locally owned installer that has been profitable for a decade may be more stable than a national brand that has been losing money for three years. Ask the question and evaluate the answer on its merits.

Have you ever had a contractor’s license suspended or revoked in any state?

A direct question most homeowners do not think to ask. A reputable installer answers it directly and without discomfort. Evasion, deflection, or irritation at the question itself is a significant signal about how the company handles accountability.

How many Xcel Energy interconnection applications have you submitted, and what is your typical timeline for Permission to Operate?

This Minnesota-specific question reveals how familiar the installer is with Xcel’s process. An installer who has submitted hundreds of applications typically achieves faster PTO — four to six weeks — than one navigating the process for the first time. The typical Xcel PTO timeline is four to eight weeks for residential systems in 2024–2025. An installer who consistently achieves the shorter end has built the documentation quality and process relationships to do it.

Will your own employees install my system, or do you use subcontractors?

Neither answer is automatically disqualifying. Some excellent installers use in-house crews exclusively. Others work with long-term subcontractor teams they have trained and vetted. What matters is accountability: if subcontractors are used, are they covered by the installer’s workmanship warranty? How long has the installer worked with those crews? Are the subcontractors licensed in Minnesota?

Who is the licensed electrician on my project?

The electrical connection between the solar system and the home’s panel must be performed by or under the direct supervision of a licensed electrician in Minnesota. The homeowner has the right to know who that person is before installation begins. A name and license number should be provided without treating the question as unusual.

What happens if my roof is damaged during installation?

Roof penetrations are required for most panel mounting systems. Done correctly, they are weathertight for the life of the system. Done carelessly, they create leak points that may not appear for months. Ask specifically: what is the sealing process for roof penetrations? What is the installer’s liability if installation causes a leak? What is the claims process? Minnesota’s freeze-thaw cycles are harder on roof penetrations than milder climates — which makes this question more relevant here than in most states.

Do you pull permits for every installation?

Unpermitted solar installations create problems with home insurance, resale, and utility interconnection. There is no legitimate reason to skip a permit. Any suggestion that permits are optional, slow things down unnecessarily, or can be skipped to save time is a significant red flag — not a favor to the homeowner.

Who will be my point of contact from signing through Permission to Operate?

The homeowner should get a named person with direct contact information — not a general customer service line. Changes in who is responsible for a project mid-process are a common source of homeowner frustration. Establish this at the start.

What specific panels and inverter are you proposing, and why?

The homeowner should know the exact manufacturer and model number of every major component before signing. “High-quality panels” or “tier-1 equipment” are marketing terms, not product specifications. Ask for manufacturer names and model numbers, then spend ten minutes researching those products: efficiency rating, warranty terms, and whether the manufacturer is still actively producing and supporting the product line.

Are the panels you are proposing still in active production?

LG exited the solar panel market in 2022. Homeowners with LG panels now hold 25-year production warranties from a company that no longer manufactures solar panels — uncertain territory for long-term support. This is not a common scenario, but it illustrates why the question matters. Panels from a manufacturer with a stable market position and active production reduce that specific long-term risk.

What inverter type are you recommending — string inverter or microinverters — and why is that the right choice for my roof?

String inverters cost less and work well on simple, unshaded roofs with a single orientation. Microinverters cost more but provide panel-level optimization and monitoring — which matters significantly on roofs with partial shading, multiple orientations, or complex layouts. The right choice depends on the specific roof. An installer who recommends the same inverter type for every home regardless of conditions is not optimizing for the homeowner.

What warranties apply to the equipment, and who do I contact for each type of problem?

Three separate warranty relationships apply to a solar installation. Panel production warranties — typically 25 years — are backed by the panel manufacturer. Inverter warranties — typically 10 to 12 years for string inverters, up to 25 years for microinverters — are backed by the inverter manufacturer. Workmanship warranties — typically 10 years — are backed by the installer. A panel that stops producing goes to the manufacturer; a roof leak at a mounting point goes to the installer. These are three different companies with three different claims processes.

What is the total installed cost, itemized by equipment, labor, permits, and interconnection fees?

A reputable installer provides an itemized quote with separate line items. The homeowner won’t negotiate individual line items, but seeing the breakdown enables meaningful comparison across quotes and a clear understanding of what the money covers. A reasonable installed cost in Minnesota in 2024–2025 is $2.80 to $3.50 per watt before incentives.

If I am financing, what is the total cost of the loan including all interest — not just the monthly payment?

A monthly payment comparison to the current utility bill is not a financial analysis. As covered on the cost page, a 20-year loan at 7% on $18,900 carries approximately $16,300 in total interest — nearly doubling the effective cost of the system. Evaluate total cost over the full loan term.

What happens to my loan payment if I do not apply the federal tax credit to the principal within the required timeframe?

Many solar loans are structured with a lower initial payment that assumes the homeowner will apply the federal tax credit — approximately $8,100 on a $27,000 system — to the loan principal within 12 to 18 months. If that does not happen, the monthly payment recalculates upward, sometimes by $50 or more per month. Any installer offering financing should explain this mechanism clearly and without prompting. If the homeowner has to ask, that is informative.

What is the payment schedule relative to project milestones?

A payment schedule that requires most of the money before installation creates misaligned incentives. A reasonable schedule ties payments to milestones — deposit at contract signing, payment at installation completion, final payment at Permission to Operate. The specific structure varies by installer, but the principle is consistent: the homeowner retains meaningful leverage until the project is complete.

What does the workmanship warranty actually cover, and for how long?

Ten years is the industry standard. The length matters less than the specificity. Does the warranty cover roof penetration leaks? Electrical connections? The racking system? What is the process for filing a claim? A warranty that covers “workmanship” without defining what that includes is not something the homeowner can rely on when a problem appears at year seven.

What happens to my warranty if your company is acquired or goes out of business?

This is the question most homeowners do not ask and most regret not asking. A reputable installer has a clear answer — warranty obligations that transfer to any acquiring company as a condition of sale, independent warranty insurance that survives the company, or honest acknowledgment with options. An installer who dismisses the question as unlikely or has no answer at all has not thought about long-term accountability.

Do you have a service department, or do you refer service calls to a third party?

Ask specifically: if the inverter fails in year eight, what is the process? Who comes to the house? How long does it typically take from service call to repair? An installer who can describe this process in concrete terms has built it. One who cannot has not. Neither in-house nor third-party service is disqualifying — what matters is whether the process exists and is clearly described.

How do I monitor my system’s production, and what should I do if it seems low?

Most modern systems include a monitoring application showing real-time and historical production data. The homeowner should understand how to access it, what normal seasonal variation looks like, and at what point underperformance warrants a service call. An installer who explains the monitoring system during the sales process is signaling that they expect an ongoing relationship with the homeowner.

Can you provide references from Minnesota homeowners whose systems have been operating for at least five years?

Recent customer references are easy to produce and tell the homeowner relatively little. References from homeowners five or more years post-installation reveal how the installer handles long-term service — responsiveness to questions, warranty claim handling, and whether the system is performing as originally estimated. An installer that cannot provide references at this tenure either has not been operating long enough or does not have satisfied long-term customers. Both are informative.