HHM demand-led research
How to compare rooftop solar quotes, financing, and payback
Solar proposals are only comparable when they use the same goals and clearly state system size, equipment, roof work, modeled production, utility assumptions, degradation, shade, cash price, financing cost, incentives, warranties, and ownership terms. Savings depend on the household’s usage, the site, the system, the purchase or lease structure, utility rates, and how exported electricity is credited. Compare the unfinanced cash price first, then evaluate each loan, lease, or power-purchase agreement separately. A realistic payback model should include likely production changes, roof timing, maintenance, insurance, fees, and more than one future-rate scenario.
What matters first
- Roof age, condition, orientation, slope, shade, structural limits, local rules, and available roof area determine whether the proposed design is practical.
- Compare system size in kilowatts, first-year production in kilowatt-hours, equipment models, degradation, shade assumptions, and production guarantees—not just panel count.
- Separate the cash price from loan principal, dealer fees, interest, lease escalators, prepayment rules, liens or security interests, and transfer obligations.
- Incentives, interconnection, export compensation, permitting, and utility rules vary by location and timing; verify the current terms before relying on projected savings.
Verify before spending
- 1Collect recent electricity bills, note planned changes such as an electric vehicle or heat pump, and confirm roof age, shade, and expected reroofing timeline.
- 2Request multiple itemized proposals showing cash price, system size, exact equipment, layout, production model, assumptions, warranties, project schedule, permits, and interconnection work.
- 3Verify installer licensing, insurance, references, complaint history, subcontractors, workmanship coverage, equipment warranty service, and responsibility if promised production is missed.
- 4Recalculate annual savings and payback using current utility tariffs and conservative production and rate scenarios, then read every financing, cancellation, transfer, and roof-work term.
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