Questions to Ask Before Signing Any Solar Contract on Long Island

Why this list exists

Long Island Solar Installation Pros provides solar installation help — we are not a licensed installer. This list is the same one we work through when reviewing a homeowner's existing solar proposal. The goal is to surface the questions that most pre-sale solar conversations skip over because they slow the close.

No reputable installer should refuse to walk through these questions. If they do, that itself is the answer.

Roof and equipment questions

What is the remaining useful life of my roof, and have you confirmed it on site? If your roof has fewer than ten years left, scoping a re-roof before installation almost always saves money over removing-and-reinstalling panels later. An honest installer will say so.

Which exact panel and inverter models are you proposing, and what are the manufacturer warranties? Spec drift between proposal and install is common — the proposal you signed should match the equipment that ships.

How did you model shade per roof plane? A single tree on the southwest corner can move annual production by 10%+. If shade is not modeled per plane, the production estimate is a guess.

If a battery is included: which exact battery model and size, and what is the backup loadcenter configuration (critical-loads vs whole-home)?

Production-estimate questions

Show me the assumptions behind the annual kWh production estimate. Tilt, azimuth, shade derating, soiling derating, equipment derating — these all roll into a single annual number that is easy to inflate on a proposal.

How does the production estimate compare to my actual 12-month PSEG Long Island (or Freeport Electric, etc.) usage? An oversized system generates credits whose value depends on the rate plan; an undersized system leaves money on the table.

What happens if production falls short of the estimate over time?

Financing fine-print questions (the most important section)

If you are being offered $0-down financing: ask to see the loan reamortization clause in writing. Many existing $0-down solar loan structures assumed the IRS Residential Clean Energy Credit would apply and would be paid down against principal within ~18 months. The federal credit applied to qualified property installed from 2022 through December 31, 2025 and is not available for property placed in service after that date — so a 2026-installed system funded by an older $0-down product may not benefit from the credit the loan structure assumed.

What is the dealer fee on this financing? Solar loans often include a dealer fee buried in the system price. It is usually disclosed if you ask directly.

What is the all-in monthly payment for the first 18 months and after the reamortization point? Get both numbers in writing.

For leases or PPAs: who keeps any active federal or state incentive? Almost always the leasing company. Make sure the math you are looking at reflects that.

PSEG / utility-specific questions

Which electric utility serves my address? If the answer is "PSEG Long Island" but you live in the Village of Freeport, the proposal is wrong before it starts. Freeport Electric, Rockville Centre Electric, and Greenport Municipal Light are separate municipal utilities — see our utility-comparison resource.

Will my system be eligible for the PSEG Long Island Battery Storage Rewards program (if a battery is included)? Which aggregator are you using, and are they accepting new participants right now?

Will the proposal recommend a Time-of-Day rate plan, and have you modeled my savings on both flat and Time-of-Day rates?

Permitting and timeline questions

Which town or village permitting jurisdiction applies for my address? Some boundaries are not obvious — for example, Patchogue addresses split between Village of Patchogue and Town of Brookhaven jurisdictions.

What is the realistic end-to-end timeline from signed contract through permission to operate? The roof install itself is usually 1–2 days; the full sequence (permit application, install, electrical inspection, utility interconnection, permission to operate) is typically several weeks.

Do you have recent project references in my town? Town-specific permitting experience matters more than total project count.

After-the-install questions

Who handles warranty service if a panel or inverter fails three years from now? The installer? The equipment manufacturer? Walk through the actual claims process before signing.

How am I notified if the system underperforms? Are there monitoring alerts, and who responds to them?

If I sell the home before the loan is paid off, what is the transfer process? This is a real question for homeowners on a 5–10 year horizon.

Incentives change and eligibility varies — confirm details with the program administrator and a qualified tax professional.