To buy solar panels for your home, work in this order: pull 12 months of electricity use, check the roof and your utility’s rules, choose whether you will own (cash or loan) or rent (lease or PPA), get at least three written quotes for the same job, verify the installer, then sign only when the contract matches the proposal. After signing come permits, installation, inspection and the utility’s permission to operate. One 2026 change affects every budget: the 30% federal homeowner tax credit does not apply to systems installed after 2025.
Installer or DIY?
Panels and kits are easy to buy online, which is why many search results for “buying solar panels” are shops. For a grid-connected system on the house you live in, the panels are the easy part. The hard parts are the electrical work, roof attachments, permit, inspection and utility interconnection approval, and mistakes in any of them are expensive. Check whether the panel and inverter warranties require installation by a licensed or certified installer before going DIY. Small off-grid projects (a shed, a cabin, an RV) are where DIY usually fits. The rest of this guide assumes a professionally installed, grid-connected home system.
1. Start with 12 months of electricity use
Your annual kilowatt-hours (kWh), not your square footage, set the system size. Two 2,000-square-foot houses can need very different systems if one has gas heat and the other has a heat pump, pool pump or EV charger. Find the 12-month total on your bills or utility account, and note anything that will change it (an EV, heat pump, addition or new baby).
Example: is 10 kW enough to run a house?
The average U.S. residential customer bought 10,791 kWh of electricity in 2022, according to the U.S. Energy Information Administration, about 899 kWh a month. Suppose a production estimate for your roof shows 1,300 kWh per year for each kW of panels (a made-up figure for illustration; your number depends on location, tilt, direction and shade). Then:
- A 10 kW system would make about 13,000 kWh a year (10 × 1,300), more than that average household uses.
- Covering 10,791 kWh would take about 8.3 kW (10,791 ÷ 1,300).
Run your own address in the free PVWatts calculator, and see how many solar panels you need for the panel count.
2. Check the roof and site
- Before committing to a system size, check where solar panels can be installed on your property: roof faces, shade, ground-mount space and any setbacks.
- Find the roof’s age. If it will need replacing within the next several years, do the roof first; DOE notes that installing solar at the same time as a roof replacement can save money, and removing panels later costs extra. Metal roofs have their own attachment options; see solar panels on a metal roof.
- Look at your main electrical panel. An older or full panel may need an upgrade, which should be priced in every quote.
- Condo owners and HOA members should confirm who controls the roof before asking for bids.
3. Learn your utility’s and state’s rules
The same system can be a good or a weak deal one state over. Before comparing quotes, look up three things:
- Export credit. What the utility pays for electricity you send to the grid (full net metering, a lower export rate, or something else), and which fixed monthly charges stay on your bill. This changes the right system size and whether a battery makes sense. Ask the utility directly.
- State and utility incentives. Rebates, state tax credits and performance payments vary widely and change on their own schedules. See EcoGen’s solar incentives by state.
- Property and sales tax. Some states exempt solar from property-tax reassessment or sales tax; check your state’s rules before trusting a savings figure.
A savings projection built on rules your utility does not have is the most common way a good-looking proposal turns out wrong.
4. Decide whether you will own or rent the system
Cash and loans buy the system; leases and power purchase agreements (PPAs) rent the equipment or buy its electricity. That choice decides who maintains the system, who can claim any tax credit and what happens when you sell the house.
Path | Who owns it | Repairs and upkeep | Federal credit for a 2026 install | When you sell the house | Compare first |
|---|---|---|---|---|---|
Cash | You | You, using the manufacturer and installer warranties | No 30% homeowner credit | The system is part of the house; no third-party contract to transfer | Price per watt, included work, payment schedule |
Solar loan | You; the lender may file a lien on the panels | You, using the warranties | No 30% homeowner credit; do not plan a “tax-credit prepayment” | Pay off or transfer the loan and clear any lien | Cash price vs financed amount, APR, fees, total of payments, payment step-ups |
Lease | The leasing company | Usually the company, per the contract | Any business credit is the company’s | The buyer takes over the lease with the company’s approval, or you buy it out | Monthly payment, escalator, term, transfer, buyout, end of term |
PPA | The solar company | Usually the company, per the contract | Any business credit is the company’s | Same as a lease | Starting rate per kWh, escalator, transfer, buyout, end of term |
The Consumer Financial Protection Bureau found in 2024 that hidden “dealer fees” on solar loans typically ran 10% to 30% of the cash price and sometimes more than 50%, and that many loans raised the monthly payment unless the borrower prepaid about 30% of the loan, the old tax-credit amount. Always ask for the cash price next to any loan offer. PACE financing works differently: the FTC notes it places a property-tax lien on your home, repaid through your property-tax bill, which can affect refinancing or a sale. EcoGen’s solar financing guide compares loans, leases and PPAs in detail, and “free” solar offers explains what no-cost offers usually are.
2026 federal tax credit: the IRS says the Residential Clean Energy Credit (Section 25D) is not allowed for expenditures made after December 31, 2025, and an expenditure counts as made when installation is completed. A system finished in 2026 does not qualify, even if you paid in 2025. A proposal that subtracts 30% from your price is wrong. For a lease or PPA, the company that owns the system may claim a separate business credit with its own deadlines (under IRS Notice 2025-42, solar projects that start construction after July 4, 2026 must be in service by the end of 2027); that credit is the company’s, and it helps you only if it shows up in the written price. If you have an unused 2025 credit to carry forward, see the federal solar tax credit guide.
5. Get at least three written quotes and compare them on the same basis
Prices for similar systems vary between installers, and three itemized quotes are usually enough to show which price or production estimate is the outlier. The FTC recommends getting detailed written bids from several companies that show system size and output, full cost including permits and fees, warranties and any production guarantee.
- Confirm every design uses the same annual usage and planned loads from step 1.
- Divide each cash price by the system’s watts to get price per watt.
- Compare first-year production in kWh and the assumptions behind it.
- Record exact panel, inverter, mounting and battery models; review the components in a home solar system before approving them.
- List exclusions and allowances: main-panel work, roof repairs, trenching, tree work.
- Read product, power-output and workmanship warranties as separate promises.
- Check the savings chart’s utility-rate increase assumption; the FTC warns that future rates are hard to predict.
The solar quote guide walks through a filled two-quote comparison. For what systems cost in your state, see solar panel cost by state; for whether the numbers work where you live, see are solar panels worth it.
6. Verify the installer, not just the price
- Look up the contractor or electrical license with the state or local board that issues it.
- Confirm who signs the contract, who actually installs (own crews or subcontractors) and who services the system afterward.
- Ask for proof of insurance and references for similar roofs and equipment.
- Check complaints with your state attorney general or consumer-protection office as well as online reviews.
- Ask how long permits and utility approval usually take in your town. A company that works locally will know.
Take the questions to ask a solar installer to each consultation and read the solar scam red flags before the first sales visit. EcoGen’s state solar company guides are a starting point if you need more bidders.
7. Review and sign the contract
- The contract matches the proposal and anything promised verbally.
- Cash price, financed amount and total of payments are all written down.
- Exact panel, inverter, mounting and battery models are named, with a rule for substitutions.
- Production and utility-rate assumptions are visible.
- Excluded work and possible change-order items are listed.
- The payment schedule ties the final payment to a milestone you can verify, such as passed inspection.
- Cancellation, transfer, service and warranty responsibilities are clear.
- You have a complete copy before signing, not just an electronic signature screen.
Stop if you are rushed, told an offer expires today, promised “free” solar, or told a government or utility program guarantees the deal. If you sign at home, the FTC’s Cooling-Off Rule generally gives you three business days to cancel covered door-to-door sales over $25, with exceptions; check the cancellation section of your own contract for the exact deadline.
8. Design, permits, installation and inspection
Design and approvals
Final site survey, engineering, building and electrical permits and the utility interconnection application. Any design or price change should come as a written change order.
Installation
DOE says the installation itself generally takes only a few days, while permits and inspections can take weeks to months depending on local rules. Before the final payment, check that the installed model numbers match the contract.
Inspection
The local building or electrical inspector checks the work. See solar permits and inspections for the full sequence and common delays.
9. Permission to operate, then keep the paperwork
The utility’s permission to operate (PTO) is when a grid-connected system may legally run; do not switch it on before then unless the utility says so. Keep the contract, final equipment list, permit and inspection sign-offs, PTO letter, warranties and monitoring login together. You will need them for warranty claims, insurance and a future home sale.
Buying a house that already has solar?
Ask the seller whether the system is owned outright, financed or leased. An owned system comes with the house; ask for the documents in step 9. A financed system may have a lien that must be paid off or cleared at closing. A lease or PPA must be transferred to you, usually with the company’s approval, or bought out by the seller. The solar lease transfer and buyout guide explains those options.
Compare the same system, not the monthly payment. Ask each installer for an itemized written proposal with a cash price, exact equipment models and a production estimate based on your 12 months of usage.
Sources
- Internal Revenue Service, energy-credit FAQ under Public Law 119-21 (Section 25D cutoff and installation-completed rule). Accessed October 14, 2026.
- Internal Revenue Service, Residential Clean Energy Credit. Accessed October 14, 2026.
- Internal Revenue Service, Notice 2025-42 (beginning-of-construction rules for Sections 45Y and 48E). Accessed October 14, 2026.
- Consumer Financial Protection Bureau, “Issue Spotlight: Solar Financing” (2024). Accessed October 14, 2026.
- Federal Trade Commission, “Solar Power for Your Home”. Accessed October 14, 2026.
- Federal Trade Commission, Cooling-Off Rule, 16 CFR Part 429 (eCFR). Accessed October 14, 2026.
- U.S. Department of Energy, “Walk Me Through It: A Step-by-Step Guide for Consumers Going Solar”. Accessed October 14, 2026.
- U.S. Energy Information Administration, “How much electricity does an American home use?”. Accessed October 14, 2026.
- National Laboratory of the Rockies, PVWatts Calculator. Accessed October 14, 2026.
