Key points
- Get at least three quotes for a similar-sized system, and make sure at least one is based on an onsite inspection.
- Compare like for like: panel and inverter models, system size in kW, expected kWh per year and price per watt after discounts.
- Approved Sellers under the New Energy Tech Consumer Code must show the deposit, total price, any STC discount and possible extra charges, and keep the price valid for at least 10 business days.
- If the sale came from a door-knock or cold call, you have a 10-business-day cooling-off period. Walk away from anyone who pressures you to sign today.
To compare solar quotes properly, line them up item by item: the exact panels and inverter, system size, expected yearly output, total price after the STC discount, extra charges, warranties, who installs it and the payment terms. The cheapest quote is often missing something, and the most expensive isn’t always the best. These 12 checks are based on guidance from Solar Victoria, the ACCC and the New Energy Tech Consumer Code (NETCC), the industry code most reputable retailers sign.
How to compare solar quotes: before you start
Before you start, collect at least three written quotes for a similar-sized system, as Solar Victoria recommends. Then work through each check below. This checklist is part of our complete guide to buying home solar panels.
Checks 1–4: are you comparing the same system?
1. Is the system the same size?
The ACCC advises making sure the quotes you compare are for the same size of system. Check two numbers: panel capacity in kW (for example 6.6 kW) and inverter capacity (for example 5 kW). A cheaper quote for 5 kW of panels isn’t comparable with a 6.6 kW quote.
2. Are the exact panel brand, model and wattage listed?
“Tier 1 panels” or “premium panels” is not enough. Under the NETCC, Approved Sellers must list the manufacturer, model, quantity and specifications. With the model number you can check it is on the Clean Energy Council approved list and read the warranty. Our guide to the best solar panels in Australia for 2026 explains what to look for.
3. Which inverter, and is it the right type?
Check the inverter brand, model and size, and whether it is a string, hybrid or microinverter system. A hybrid inverter costs more but saves money later if you plan to add a battery. Microinverters cost more but suit shaded roofs. Read our comparison of string, hybrid and microinverters.
4. Is there a site-specific design and output estimate?
For a custom installation, the NETCC requires a site-specific design (a sketch or roof layout is fine) and a site-specific performance estimate. Solar Victoria says a quote should state expected yearly production in kWh. Use it as a sanity check. A well-oriented, unshaded 6.6 kW system produces roughly:
- Adelaide: about 10,100–10,600 kWh a year (4.2–4.4 kWh per kW per day)
- Melbourne: about 8,700–9,200 kWh a year (3.6–3.8 kWh per kW per day)
East-west roofs and shading will lower these figures. An estimate well above them deserves a question.
Checks 5–7: price, extra charges and warranties
5. What is the total price after discounts?
Every quote should show the full price including GST, the deposit and the value of any STCs, rebates or incentives, and how they apply. In 2026 a 6.6 kW system creates about 45 STCs in Adelaide and about 39 in Melbourne, worth roughly $1,800 and $1,550 at current prices. If one quote shows a far smaller STC discount, ask why. Victorian quotes should also show the Solar Homes rebate of up to $1,400 if you’re eligible.
Then calculate the price per watt: divide the price after discounts by the panel capacity in watts. For example, a hypothetical $5,900 quote for 6,600 W works out at about 89c per watt, and a $7,400 quote with microinverters at about $1.12 per watt. That shows the premium you’re paying for the better equipment.
6. What extra charges could apply?
The NETCC requires quotes to spell out site conditions that could lead to extra charges. Common ones include:
- Switchboard upgrades or replacing old ceramic fuses
- Meter exchange or reconfiguration fees from your retailer
- Double-storey or steep-roof access, scaffolding
- Tile roofs, Klip-Lok roofs or tilt frames
- Three-phase connection or long cable runs
A quote that looks cheap but leaves these as “to be confirmed” may end up costing more.
7. What warranties come with it?
Compare four separate warranties:
| Warranty | Typical in 2026 | What to check |
|---|---|---|
| Panel product | 12–25 years | Australian office and claims contact |
| Panel performance | 25–30 years | Output guaranteed at the end, often about 87–89% |
| Inverter | About 10 years (up to 25 for some microinverters) | Whether labour is covered |
| Installation (workmanship) | Varies by retailer | Length, what’s covered, who you call |
Solar Victoria notes that panels are typically covered for about 25 years and inverters for about 10, and that the installer should also give an installation warranty. Your rights under the Australian Consumer Law apply on top of any written warranty.
Checks 8–12: the installer, approvals and contract terms
8. Who will actually do the installation?
The installer must be accredited by Solar Accreditation Australia (SAA) and the electrical work done by a licensed electrician. Ask whether the retailer uses its own team or subcontractors, and check the installer’s accreditation on the SAA website.
9. Is the retailer an Approved Seller?
Over 2,000 retailers have signed the NETCC as Approved Sellers, which commits them to standards on sales, contracts, warranties and complaints. Check the quote shows a full business name, ABN, physical address and phone number. In Victoria, the retailer must be authorised by Solar Victoria for you to claim the Solar Homes rebate. An updated version of the code takes effect on 1 December 2026, with more detail on fees and refunds for custom design work.
10. Who arranges network approval, and what export limit is assumed?
Under the NETCC, the quote must offer to arrange network approval and meter changes, explain the steps and say what charges may apply. Check what export limit the savings estimate assumes. In SA, for example, a fixed limit is normally 1.5 kW per phase, while SA Power Networks’ flexible exports allow up to 10 kW per phase. Our guide to the solar installation process explains each approval step.
11. What are the payment terms?
Check the deposit, when the balance is due and what happens to your deposit if the contract is cancelled or network approval is refused. Approved Sellers must give a receipt for any deposit. If you’re offered finance, the NETCC requires the credit provider’s name, the total cost compared with paying cash, and all fees. “Interest-free” plans can carry higher prices or fees, so compare the total. Our guide to solar finance options compares loans, interest-free plans and cash.
12. Are you being rushed?
Approved Sellers must keep quote prices valid for at least 10 business days and must avoid high-pressure tactics, such as claiming “community” or bulk-buy discounts that don’t exist, pushing you to decide on the spot, or repeated uninvited calls and visits. If the sale started with a door-knock or cold call, you have 10 business days to cancel without penalty under the Australian Consumer Law. See our list of solar scam red flags.
A simple solar quote comparison table
Copy this table and fill in one column per quote:
| Item | Quote A | Quote B | Quote C |
|---|---|---|---|
| Panel brand, model, wattage, number | |||
| System size (kW panels / kW inverter) | |||
| Inverter type and model | |||
| Expected output (kWh/year) | |||
| Price after STCs and rebates | |||
| Price per watt | |||
| Possible extra charges | |||
| Warranties (panel / inverter / installation) | |||
| Onsite inspection done? | |||
| Approved Seller / SAA installer? | |||
| Deposit and payment terms |
What if two quotes are almost the same price?
Solar Victoria suggests that when prices are similar, you look at warranty length, online reviews and the installer’s experience. We’d add two more: how clearly the retailer answered your questions, and whether they visited your home. A retailer who takes the time to explain the design before the sale is more likely to look after you afterwards.
Frequently asked questions
How many solar quotes should I get?
Get at least three written quotes for a similar-sized system, as Solar Victoria recommends. Make sure at least one retailer inspects your roof and switchboard in person. More than four or five quotes rarely adds value and can make like-for-like comparison harder.
Why is one solar quote so much cheaper than the others?
Usually because of cheaper panels or inverters, missing extras such as switchboard work, a shorter workmanship warranty, or subcontracted installers. Sometimes it is simply lower margins. Compare the exact models, extra charges and warranties side by side before assuming the cheapest is the best deal.
What is a good price per watt for solar in 2026?
Prices vary with equipment and roof complexity. As a guide, typical 2026 market prices for a 6.6 kW system are roughly $4,500–$8,000 after STCs, or about 70c to $1.20 per watt. Premium panels, microinverters and difficult roofs push the price higher. Treat these as indicative ranges only.
Can I cancel a solar contract after signing?
If the sale started with an unsolicited door-knock or phone call, you have 10 business days to cancel without penalty under the Australian Consumer Law. For other sales, check your contract’s cancellation terms before signing. Approved Sellers must explain any cancellation fees, and those fees must be reasonable.
We’re happy to be one of your three quotes. Our Adelaide and Melbourne team provides a written, itemised quote with a site-specific design for every home solar package. Get a free quote and compare it against the checklist above.
Sources: Solar Victoria – What to look for in a solar quote (updated 6 Mar 2026); ACCC – Solar panel systems and home batteries; New Energy Tech Consumer Code; New Energy Tech Consumer Code – Moving to an updated code (effective 1 Dec 2026); Clean Energy Council – Choosing a retailer or installer. Prices and rules change; check current details with Solar Victoria, the ACCC and the retailer. Featured image: David Hawgood / Wikimedia Commons, CC BY-SA 2.0.
