A solar proposal is built to look impressive, not to be easy to compare. Here is a plain-English walkthrough of every line so nothing gets past you, and so you can tell a fair bid from a padded one.
The first real number on any quote is the system size, written in kilowatts (kW). It is simply the sum of all the panels multiplied by their wattage. A 7.2 kW system might be eighteen 400-watt panels. Size matters because every other figure on the page flows from it, and because two installers will often propose different sizes for the same roof. A bigger system is not automatically better; it is only better if you actually use that much electricity. Compare the proposed size against your real annual usage, which any honest quote will reference from your past bills.
Total price is the number installers want you to focus on, but price per watt is the number that lets you compare bids fairly. Take the total system price and divide it by the system size in watts. A $21,000 quote on a 7,000-watt system is $3.00 per watt. Doing this for all three of your quotes puts them on the same footing even when the system sizes differ. Calculate it on the price before the tax credit, because the credit applies the same way to every honest bid and can otherwise be used to make an expensive quote look cheap.
This section lists the brand and model of your panels and inverter, plus the warranty terms. Read it closely. A low price paired with off-brand equipment and a short warranty is not actually a deal. Look for three separate warranties: the product warranty on the panels, the performance warranty (how much output is guaranteed over 25 years), and the workmanship warranty on the installation itself. The workmanship warranty is the one homeowners forget, and it is the one that protects you if a roof penetration leaks two years later.
Every quote includes an estimate of how much electricity the system will produce in a year, usually in kilowatt-hours (kWh). This number drives the savings claims later in the document, so it is worth scrutinizing. Ask what software produced it and whether it accounts for your roof's actual orientation, tilt, and shading. An installer who inflates the production estimate can make a system look like it covers more of your bill than it really will. When you compare quotes, line up the production estimates next to the system sizes; a much higher estimate on a similar-sized system is a flag to question.
How you pay changes the entire economics of the deal, and this is where proposals get slippery.
Make every quote show you the financing terms in writing: the interest rate, the term length, any dealer fee, and the escalator if there is one. A verbal "your payment will be about the same as your bill" is not a term you can hold anyone to.
Quotes often fold the federal solar tax credit and any state or utility incentives directly into the headline savings. The credit is a real benefit for homeowners who buy their system, but it is claimed when you file your taxes, not handed to you at signing, and it only helps if you have the tax liability to use it. Treat any line that subtracts the credit up front as a projection. Have each installer state plainly which incentives apply to your specific address and how they are claimed, then compare those claims across your three bids.
The big "you'll save $X over 25 years" figure is the most persuasive line on the page and the least reliable. It is built on assumptions the installer chose, chiefly how fast they expect your utility rate to rise and how much the system will produce. Small changes to those inputs swing the total dramatically. Use the savings number as a sanity check, not as the basis for your decision. Anchor on the firm price, the price per watt, and the equipment quality, all of which are facts rather than forecasts.
Before you compare totals, find out what each quote leaves out. Common omissions that show up as surprise costs later include a main electrical panel upgrade, roof repairs or reinforcement, and trenching for ground mounts or long conduit runs. If any of these appear as an "allowance" rather than a fixed price, that is a placeholder that can grow. Also check the installation timeline, the permitting and interconnection responsibilities, and whether removal and reinstallation for a future roof replacement is covered.
The single best way to read a solar quote is to never read just one. A proposal in isolation gives you no reference point, which is exactly how overpriced systems get sold. When you lay three competing bids for the same roof next to each other, the padded price per watt, the inflated production estimate, and the buried dealer fee all become obvious. That is the entire reason this service exists. Submit your home once and three vetted local installers send competing estimates you can compare line by line, free.
Price per watt. Divide the total system cost by the system size in watts so you can compare bids of different sizes fairly. Look at it before the tax credit, since the credit applies equally to every honest bid.
Savings figures rely on assumptions the installer chooses, like future utility rate increases and production. They are projections, not guarantees. Anchor your decision to the firm price and equipment, then treat savings as a sanity check.
Dealer fees baked into financed deals, payment escalators on leases and PPAs, separate charges for a main panel upgrade, and roof or trenching work listed as an allowance instead of a fixed price. Ask for every line itemized in writing.
You cannot judge one quote alone. Put three competing bids for the same roof side by side. We gather three for you free so you can compare price per watt, equipment, and terms.
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