How to Compare Solar Quotes

Quick Summary

Why This Matters

Solar proposals can look deceptively similar. But what’s hidden beneath the numbers — assumptions, financing structures, or service commitments — is what determines whether your system delivers real long-term value.

In Western Massachusetts, where electric rates are high and reliability matters, homeowners should think service first and evaluate every quote on credibility, not just cost.

What to Know Before You Start

Every solar quote should include: 

• System size (kW): How much solar capacity is proposed.
• Estimated annual production (kWh): What the system is projected to generate.
• Equipment & warranties: Panel and inverter brands, plus coverage details.
• Pricing & incentives: Check that incentives and tax credits are shown consistently.
• Financing: Lease, loan, or cash purchase — watch for hidden fees.
• Timeline & permitting support: Who handles the paperwork.
• A good visual of the design:  You should see what the irradiance is for each array, and whether the design prioritizes your best roofs first. 

Red Flags to Watch For: 

• Dealer fees buried in loans. A “0% financing” pitch often hides large dealer fees added to your loan principal.
• Assumed electric rates. If one installer uses $0.40/kWh and another uses $0.30/kWh, the savings projection can differ dramatically even for identical systems. Always confirm the rate matches your actual bill.
• Inflated production estimates. Many installers use outdated tools and exaggerate. Always ask how estimates are calculated — and demand a written production guarantee.
• Designs that don’t make sense:  Make sure the solar panels get the best sun.  Many companies, especially the big ones, use overseas designers who may not know the local requirements and codes. 

Step-by-Step: Comparing the Quotes

1. Normalize the Numbers
   Standardize system size, gross cost, incentive assumptions, and production estimates.
2. Scrutinize the Estimate
   Ask what modeling tools were used. Valley Solar uses advanced software and backs every estimate with a written 95% production guarantee.
3. Evaluate Financing Carefully
   Compare APR, loan term, and escalators. For leases, compare the cost per kWh you’ll pay and the annual escalator (0% vs. 3.9% is a huge difference over 20 years). Check the guaranteed production level. Some leases only guarantee 80% — leaving you with risk.
4. Check Equipment & Warranty
   Good equipment is important, but warranties only matter if the company is credible and still around when service is needed. Look for labor coverage, not just parts.
5. Think Service First
   Don’t buy into the myth that “nothing ever goes wrong.” Solar systems do require service, even without moving parts. Make sure your installer has a dedicated service department and a warranty plan that’s more than just words.
6. Check the design and really kick the tires
   Don’t be afraid to make your rep explain the design choices. Why they used certain roofs, where the fire setbacks are, why they used which inverter or battery, where the equipment will be mounted and why. If they can’t explain it, they probably don’t understand it. This is not a job for amateurs.

Helpful Tips & Watchouts

• Standardize quotes before comparing.
• Don’t be swayed by “lowest monthly payment” gimmicks.
• Check electric rate assumptions — inflated rates = fake savings.
• Compare lease quotes by kWh price, escalator, and production guarantee.
• Don’t fall for warranties without labor coverage.
• Remember: you’re not just buying hardware. You’re paying for energy in advance — service and accountability protect that investment.

Key Takeaways

• Comparing quotes is about more than price — it’s about assumptions, financing, and service.
• Service first: warranties and guarantees only matter if the company stands behind them.
• Electric rate assumptions and dealer fees can distort “savings” numbers — standardize for a fair comparison.
• Always ask how production estimates are created — and insist on a written guarantee.
• Lease or own? The right answer depends on your goals. Valley Solar offers both and gives homeowners an unbiased overview of each option.