The Solar Quote Decoder

The problem

A solar rep was at your kitchen table on Tuesday evening. He sketched panels on a notepad, ran your address through a satellite tool while you made coffee, and put a number on the table: 9.8 kW for $38,400 financed at 6.99% for 25 years, zero down, monthly payment lower than your current utility bill. The 30% federal tax credit is right there in the proposal. The 25-year savings projection at the bottom is a big green number. He needs a signature tonight because the price is custom to your roof and he cannot extend it. Your spouse is hungry. The kids need to be picked up. You have been in the living room for almost three hours.

This is the moment the funnel was engineered for. The $28,000 average residential solar contract in the United States in 2025 is a 25-year decision being closed inside a 10-to-14-day window from first knock to signature, and a typical $28K quote can be hiding $3,000 to $8,000 in oversold capacity, a dealer fee buried in the financed principal, a reamortization clause tied to a tax credit you may not be able to fully claim, an escalator on a loan you thought was fixed, or a lease structure that turns net-positive into net-negative the moment you decide to sell the house. The pressure to sign tonight is real, the rep’s incentives are real, and the math on the contract is exactly as engineered as the funnel that put you in front of it.

What most people get wrong

They treat solar like a price comparison instead of a four-product comparison. A 9 kW system at $28,000 is a single physical reality. It is also four completely different financial products depending on whether you pay cash, finance it, lease it, or sign a PPA. Most homeowners walk in thinking the decision is “which installer.” The harder decision is “which ownership structure,” and the rep will explain whichever option is most profitable for them with the most energy. Cash gets you a payback in about ten years and a +$22,900 25-year benefit. A standard solar loan at 6.99% over 20 years gets you to +$6,500 after the dealer fee eats most of the savings. A lease at a 2.9% escalator gets you to -$5,400 over 25 years. A PPA at $0.12/kWh with the same escalator gets you to -$9,000. The financing choice often matters more than the equipment choice.

They focus on the headline price instead of the per-watt price. Three bids for similar-sized systems can range from $3.18/W to $4.03/W with nothing in the equipment line items that justifies the spread. The headline number tells you what the installer wants you to focus on. The per-watt number tells you what you are actually paying. The same 8.4 kW system at $3.18/W and at $4.03/W is the same physical roof and the same monthly bill, but it is $7,140 of difference, almost all of it in soft-cost markup the installer has no obligation to explain. Soft costs (labor, permitting, sales commission, dealer fee, overhead) run 60 to 65% of the system cost in US residential solar in 2025, the highest of any developed market.

They believe the production estimate. The 25-year savings projection is built on top of an annual production estimate in kWh. If that estimate is inflated by 20%, the savings projection is inflated by 20%. The two common tricks: assume your roof faces dead south with no shade when it does not, and ignore panel degradation in the savings math. A quote whose specific yield (kWh per kW DC installed) exceeds NREL’s PVWatts default by more than 5 to 7% should be challenged in writing. A quote in Philadelphia claiming 1,500 kWh/kW DC is in desert-Southwest territory, not Mid-Atlantic territory, and that single line item often hides the gap between the contract and reality.

A working approach

The book is structured around a sequence: understand the funnel that is selling you, decode the quote line by line, compare the four financing structures, evaluate the equipment honestly, run the production math, vet the installer, scrutinize the warranties, and normalize three bids onto a single spreadsheet before you sign anything. Each chapter has the math, the line items, and the questions to ask in writing.

CHAPTER 1 — The high-pressure solar funnel
  Why the rep wants you to sign tonight; the three pressure tactics

CHAPTER 2 — Anatomy of a solar quote
  Seven sections; per-watt benchmark; the one-page quote audit

CHAPTER 3 — Cash, loan, lease, PPA differences
  25-year math on all four; $32K lifetime spread between cash and PPA

CHAPTER 4 — Panel, inverter, battery basics
  Q CELLS, REC, SunPower; Enphase IQ8, SolarEdge HD-Wave; Powerwall 3

CHAPTER 5 — Production claims and usage math
  Run PVWatts yourself; right-size for actual usage; NEM 2.0 vs 3.0

CHAPTER 6 — Installer red flags
  Four installer categories; verbal promises that never make the contract

CHAPTER 7 — Warranty and service questions
  Four warranties, three risks; the labor-coverage gap

CHAPTER 8 — The three-bid comparison method
  Per-watt normalization; weighted scoring; the 7-day decision window

CHAPTER 9 — Using trust.guide for expert review
  When $200-$500 catches a $3K-$12K mistake

Cash vs loan vs lease vs PPA, with the actual 25-year math

A 9 kW system at $28,000 gross priced four ways. Cash: $28,000 outlay, 30% federal ITC ($8,400) drops it to $19,600 net Year 0, twenty-five years of electricity savings around $45,000, an inverter replacement at year 12 around $2,500, net 25-year benefit of +$22,900 with a roughly ten-year payback. Standard solar loan at 6.99% over 20 years with a $3,000 dealer fee built into the principal: $0 Year 0 outlay, $31,000 gross, $22,600 principal after ITC application, $13,400 of total interest over 20 years, net 25-year benefit drops to +$6,500. Lease at $120/month with a 2.9% annual escalator: $0 Year 0 outlay, year 1 payment $120, year 25 payment $236, total 25-year lease payments $50,400 against $45,000 in gross savings for net 25-year benefit of -$5,400. PPA at $0.12/kWh with the same 2.9% escalator on a system producing 12,500 kWh annually: year 1 PPA payment $1,500, year 25 PPA payment $2,950, total PPA payments $54,000 against $45,000 in avoided utility electricity for a net 25-year cost of +$9,000 you are paying more than you would have without solar at all.

The cash and loan options have you owning the system and claiming the 30% federal ITC. The lease and PPA have a third party owning the system and capturing the credit. That single difference cascades into the home-sale process: roughly 25% of homebuyers refuse to assume an existing solar lease, leaving the seller with a $15,000 to $25,000 buyout decision at the moment they were trying to close. The book covers a real Colorado case where a four-year-old SunRun lease cost $18,400 to buy out at sale against an undepreciated retail value of around $14,000. The lease was sold in 2019 as $8,200 of projected 25-year savings. The math the rep showed in 2019 did not account for the exposure.

The 30% federal ITC runs through 2032 under the Inflation Reduction Act with a step-down to 26% in 2033 and 22% in 2034. Any rep claiming the credit is about to expire is selling urgency that the IRA already removed. Standard solar loan APRs in 2025 run 4.99% to 9.99% depending on credit. Lease and PPA escalators run 1.99% to 3.99%. The dealer fee on a “low APR” loan is typically $3,000 to $5,000 buried in the principal, which is why the single most important question to ask any financed offer is: “What is the cash price for this exact system, with no loan?” If cash is more than 10% lower than financed, the gap is the dealer fee, regardless of what APR you were quoted.

Equipment basics: panels, inverters, batteries

The panel market has roughly 10 to 15 brands that matter for US residential. The honest tiers: premium (SunPower Maxeon at 20 to 23% efficiency with a 40-year product warranty and 92% power retention at year 25, Panasonic EverVolt heterojunction cells with a 25-year warranty), upper Tier 1 (Q CELLS Q.PEAK DUO at 20 to 21% efficiency with 25-year product warranty and 85% power retention, REC Alpha at similar terms), standard Tier 1 (Canadian Solar HiKu, Trina, JA Solar at -8 to -15% versus the upper tier), and budget Tier 1 (LONGi, Risen at -15 to -25%). The right panel is usually Q CELLS or REC. SunPower Maxeon makes sense when roof space is the binding constraint, which on most suburban roofs it is not. LG exited the panel and battery business in 2022 to 2024 with warranty administration handed to a third party with limited recourse.

The inverter is the component most likely to fail. String inverters (SMA Sunny Boy, Fronius Primo) are cheapest and best for simple unshaded roofs. Enphase IQ8 microinverters put one inverter per panel with a 25-year warranty matching the panel warranty, which is the gold standard but 8 to 15% more expensive upfront. SolarEdge HD-Wave is a hybrid: a central inverter with 12-year warranty (25 extendable for a fee) plus per-panel DC optimizers at 25 years. The central inverter on the SolarEdge typically needs replacement at year 12 to 15 at $1,500 to $2,500 plus labor, which is the line item that flips the upfront savings into a longer-run cost. Tesla’s proprietary inverter only works with Tesla Energy installations and runs on a closed ecosystem; functionally fine when it works, structurally risky.

Batteries are 25 to 40% of the total quote and most homeowners do not need one. Tesla Powerwall 3 at 13.5 kWh usable runs $11,500 to $15,000 installed with a 10-year warranty and an integrated inverter that lets it pair with any solar setup. Enphase IQ Battery 5P at 5 kWh per unit stacks 2 to 4 units typical at $5,500 to $7,500 per unit with a 15-year warranty and native Enphase IQ8 integration. The honest battery test: frequent outages of more than three per year (yes), time-of-use rates with a 3x peak-to-off-peak spread (yes), California NEM 3.0 or net billing (yes, the battery is what makes the economics work), standard NEM 2.0 with a stable grid (no, the math does not pencil). The book documents a real Atlanta case where a $13,000 Powerwall on a flat-rate utility with one outage a year captured roughly $0 in arbitrage. The same money in the S&P 500 would have compounded to about $25,000 over ten years. The battery was a comfort decision sold as a financial one.

Production math you can run yourself in five minutes

PVWatts is NREL’s free production-estimate tool at pvwatts.nrel.gov. It takes five inputs (address, system size in kW DC, tilt, azimuth, module type), runs about five minutes, and gives you the annual kWh production expected for the system on your specific roof. The installer already ran it before quoting you. The book walks the regional specific-yield norms: Desert Southwest at 1,600 to 1,750 kWh per kW DC, California at 1,450 to 1,600, Mountain West at 1,450 to 1,550, Texas and Florida at 1,300 to 1,450, Mid-Atlantic at 1,200 to 1,350, Pacific Northwest at 1,050 to 1,200, Midwest and Northeast at 1,100 to 1,250. A quote claiming a Philadelphia 9 kW system will produce 13,500 kWh annually (1,500 specific yield) is making an aggressive assumption that does not hold up; PVWatts at 14% loss default returns about 11,900 kWh (1,322 specific yield) for that roof.

The other half of the production math is your actual usage. Pull 24 months of electric bills (not 12, because a single anomalous year skews the baseline). A right-sized system produces 90 to 110% of your annual usage. Over-sizing past 110% means producing electricity that may credit at wholesale rather than retail under your state’s net metering policy. California shifted to NEM 3.0 in April 2023 with excess production crediting at $0.04 to $0.08/kWh wholesale instead of the retail rate that NEM 2.0 still pays in most states, a 60% reduction in export-credit value. Hawaii has had net billing for years. Several other states are debating similar shifts. A homeowner in San Diego in 2024 signed for a 12.6 kW system against 9,800 kWh annual usage; the installer’s projection showed $32,000 in 25-year savings; NEM 3.0 took effect on the install date and the excess 6,600 kWh annually crediting at wholesale produced $330/year in real savings instead of $2,112/year. Over 25 years the oversizing produced $8,000 in actual savings instead of the $53,000 projected.

Installer red flags and what to verify

US residential solar installer landscape divides into four categories in 2025. Solar-only specialists (local or regional, crews are employees, reputation tied to local quality) are often the best balance of cost and quality when you can find one with 5+ years and 200+ installs that has not been acquired. Roofing-and-solar combo shops make sense when you genuinely need a new roof in the next 1 to 3 years and waste money on capacity you do not need when the roof has 10+ years left. Marketplace lead-gen platforms (SunRun above 20% national market share, Sunnova, Tesla Energy, Palmetto) offer scale, broad financing, lease/PPA products, and the most aggressive sales tactics; the lease/PPA defaults are typically the worst math for the homeowner. Private-equity rollups have acquired regional installers over the past five years with mixed quality outcomes; the local brand stays the same while ownership and incentive structures change. Ask directly: “Is this company still locally owned, or has it been acquired in the last 5 years?” Evasion is itself useful information.

The verbal promises that never make the contract: “We guarantee X kWh production per year” (rarely written), “We will fix any roof leak for free” (workmanship warranty is 5 to 10 years not lifetime), “We will remove and reinstall panels for free if you need a new roof” (R&R coverage is $1,500 to $3,500 and seldom included in writing), “You can transfer the system if you sell” (true for cash and loan, requires buyer assumption for lease/PPA), “We will buy back any unused production” (that is your utility’s net metering policy, not the installer’s offer to make).

Credentials worth verifying at the certifying body’s site, not the installer’s brochure: NABCEP certification at nabcep.org (gold-standard installer credential), state contractor license (check the state board), manufacturer-certified installer (check the manufacturer’s site), BBB rating (bbb.org), SolarReviews and EnergySage ratings (solarreviews.com, energysage.com). Contract red flags to read for specifically: mandatory arbitration stripping your right to sue or join a class action, unilateral price increase if the design changes after permit approval, install timelines past 120 days with no penalty for delay, workmanship warranty under 10 years, production guarantees that exclude “acts of God, shading, or system condition” (which means they guarantee nothing), reamortization clauses on loan products, no cancellation right beyond the legally-required three-day window, UCC-1 lien filings on the property.

NEM 2.0 versus NEM 3.0

Net metering is the credit you get for excess electricity sent back to the grid. The policy is set by your state public utility commission and your local utility, not by the installer. Under NEM 2.0 (still in effect in most US states in 2025), excess production credits at the retail electricity rate, often $0.13/kWh or higher. One kWh exported is worth one kWh imported. Under NEM 3.0 (California, with several states debating), excess production credits at the avoided-cost or wholesale rate, often $0.04 to $0.08/kWh. One kWh exported is worth a fraction of one kWh imported. The shift makes oversizing economically destructive and makes battery storage essential for capturing your own excess production at retail rather than exporting at wholesale.

Any quote in California in 2025 needs to be sized for NEM 3.0. Any quote in a state with active rate-design proceedings (Massachusetts, Arizona, North Carolina, Illinois) needs to account for the possibility of a similar shift during the 25-year ownership window. The book walks the state-by-state policy landscape and the questions to ask the installer specifically about your utility’s tariff structure.

The three-bid comparison

The single discipline that protects most homeowners from the worst outcomes is the three-bid comparison normalized onto a single spreadsheet. The book includes three-bid-comparison.csv with the normalization rows pre-built: system size in kW DC, panel brand and model, inverter, battery, production estimate against PVWatts reference, specific yield, gross system cost, per-watt cost, ITC, cash price versus financed (which reveals the dealer fee), loan APR and term, monthly payment, workmanship and inverter warranties, install timeline, NABCEP certification on the install crew, reamortization clauses, written production guarantees, and references provided. The weighted score: 30% price, 20% equipment quality, 15% warranty coverage, 15% installer reputation, 10% financing terms, 10% production estimate alignment.

A real New Jersey example from the book: Bid A from SunRun at 10.4 kW with Q CELLS and Enphase IQ8 at $36,800 financed at 6.99% for 25 years, $0 down. Bid B from a local installer with 9 years and 2 NABCEP-certified staff at 8.2 kW with the same panels and inverters at $25,800 cash or $27,400 financed at 6.49% for 15 years. Bid C from a roofing combo at 9.0 kW with Canadian Solar and SolarEdge at $31,200 cash. Weighted scores: Bid A at 3.45, Bid B at 4.20, Bid C at 3.80. Bid B won not because it was the cheapest gross but because the price gap was justified by appropriate sizing for actual usage (10,800 kWh annually, not the oversized 10.4 kW Bid A was selling), better workmanship warranty (15 years vs 10), and the only written production guarantee of the three. Net 25-year savings over Bid A: roughly $10,600. Decision time from first bid to signature: nine days.

The 2025 per-watt benchmark ranges. Budget tier (standard Tier 1 panels, string inverter, no battery) at $2.50 to $3.10/W. Standard tier (Q CELLS or Canadian Solar premium, microinverter or DC optimizer) at $3.10 to $3.60/W. Premium tier (SunPower Maxeon or Panasonic, Enphase IQ8) at $3.60 to $4.50/W. Battery add-on (Powerwall 3 or Enphase 5P stack) adds $1.00 to $1.50/W system-wide. A $5.20/W quote with standard equipment is overpriced by $15,000+ on an 8 kW system. A $2.10/W quote with premium equipment is suspiciously low; the equipment is probably not what is claimed.

Closing

By the end of the book you have the framework for a 25-year decision that most homeowners make in less than two weeks. You have the line-by-line decode of the quote, the 25-year math across all four financing structures, working knowledge of which panels and inverters and batteries are oversold versus actually-worth-it, a production sanity check against PVWatts that catches the 30% over-production trick, the four installer categories and the verbal promises that never make the contract, the four warranties and where the labor-coverage gaps hide, and the three-bid comparison spreadsheet you can drop your own quotes into. The book is opinionated about one thing in particular: do not sign in the room. The three-day right to cancel is federally mandated for in-home solicitation sales. The 30% federal tax credit is in place through 2032. The funnel that put a rep at your kitchen table for three hours on Tuesday evening is engineered to overcome a buyer’s better judgment, not to reward it.

The single chapter that pays back the price of the book over and over is the independent-review chapter. A 90-minute review by a NABCEP-certified consultant or an independent energy engineer through trust.guide costs $200 to $500 and catches a $3,000 to $12,000 mistake roughly 30 to 40% of the time. The reviewer reads the quote in isolation from the sales relationship, runs PVWatts independently, opens the loan documents to find the dealer fee, reads the contract for the reamortization clause, and writes a one-page summary plus detailed findings. The expected value is reliably positive for any quote above $25,000 or any quote with a battery, a lease, a PPA, or NEM 3.0 implications. The cheapest way to lose $5,000 on a solar installation is to skip a $300 review on a $32,000 system because the review fee felt extravagant.

Included with the book

• Three-Bid Comparison Spreadsheet (CSV) — 31 normalization rows with worked example from a real New Jersey three-bid case, weighted-score grid included.
• Installer Question Checklist (markdown) — 50 questions organized into equipment, financing, production, warranty, service, and install-crew categories. Print one per installer.
• Financing Comparison Spreadsheet (CSV) — 12 financing structures pre-calculated (cash, three loan APR scenarios, HELOC alternative, three lease escalator scenarios, three PPA rate scenarios) with year-1 payment, year-25 payment, 25-year total, ownership, and tax-credit eligibility.

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Questions readers ask

Is this book US-specific?

The federal Investment Tax Credit, NEM/NEM 3.0, and dealer-fee structures are US-specific. The quote anatomy, equipment tiering, production math via PVWatts, installer red flags, warranty structures, and three-bid normalization apply broadly. International readers will need to substitute local tax incentives, feed-in tariffs, and financing products for the US-specific sections.

Will the book be obsolete when my state changes net metering?

The math gets adjusted but the framework holds. The book includes both NEM 2.0 and NEM 3.0 sizing logic specifically because the policy environment is shifting. When your state moves from net metering to net billing, you re-run the production math at the new export-credit rate; the rest of the framework (quote anatomy, financing comparison, three-bid normalization) is unaffected.

Do I need a battery?

Usually no. The book walks a four-question test: outage frequency (more than three per year argues yes), time-of-use rate spread (3x peak-to-off-peak argues yes), net metering policy (NEM 3.0 or net billing argues yes, NEM 2.0 argues no), and medical-equipment needs (often yes with a smaller battery). Most homeowners in NEM 2.0 states with stable grids do not need a battery for the math to work; the rep selling you one is selling the comfort decision.

What if I already signed?

The federally-mandated three-day cancellation window applies to any in-home solicitation sale. If you signed in your home and have doubts within 72 hours, you can cancel in writing without penalty. After the three-day window, your remedies depend on the contract terms and state consumer-protection law. The installer-red-flags chapter walks the contract clauses most likely to limit your options post-signature.

What if I need a refund?

Checkout runs on Lemon Squeezy. The standard refund window applies. You keep the PDF either way.