Screen your solar or battery quote against the same published-cost benchmarks used in this guide.
Check your quote in 2 minutes1. MCS certification and consumer code
Ask the installer to confirm that it is MCS-certified and state which consumer code it belongs to: RECC or HIES. Do not rely on a logo alone; the company named on the quotation should be the company whose status you check.
Ask when you will receive the MCS certificate and who is responsible for the paperwork. A clear answer before signing is better than trying to establish responsibility after the installation is complete.
2. Deposit, protection and the 25% check
Compare the deposit with the full contract price. If it is more than 25%, ask why it is that high and how your money is protected. The quotation should explain when the deposit is due and what happens to it if the work does not proceed.
Keep the explanation and protection details with the quote. Do not accept a verbal assurance in place of written terms that you can review before paying.
3. Itemised panels, inverter and battery
The quote should name the make, model and quantity of every panel, plus the inverter make and model. If a battery is included, it should identify the battery, usable capacity and any separate or hybrid inverter.
Model names let you compare specifications and warranties. A generic description such as 'premium panels' does not let you know what will actually be fitted or whether another quotation contains equivalent equipment.
4. System size and estimated annual generation
Check that the quotation gives the solar array size in kWp and the estimated annual generation in kWh. These are different measures: kWp describes the rated system size, while annual kWh is the forecast output.
The kWp figure is essential for checking the quote price. PowerGuardian divides the solar price by kWp and compares the result with the bands in its shared configuration; it never assumes a system size when the quote does not provide one.
5. Performance estimate method
Ask how the annual generation estimate was produced and which roof details, orientation and shading assumptions were used. The figure should be tied to your proposed layout rather than presented as an unexplained promise.
Look for a clear separation between estimated generation and claims about bill savings. Savings depend on how much solar electricity the household uses directly, what it exports and the tariffs that apply.
6. Scaffolding and access
Confirm whether scaffolding is included in the total. Ask whether the access plan covers every roof face in the design and whether any access charge could be added later.
If two quotes differ materially, scaffolding and roof access are sensible items to compare first. The cheapest headline may not be the cheapest completed installation if important access work is excluded.
7. Grid or DNO application
The quotation should say who deals with the Distribution Network Operator (DNO) and whether the required grid application or notification is included. Ask what happens if the network response affects the proposed design.
You should know who owns this task before signing. It should not be left as an undefined responsibility between the homeowner and installer.
8. Warranties and who stands behind them
List the panel, inverter, battery and workmanship warranties separately. Ask how long each lasts, what it covers, who handles a claim and whether any registration step is required after installation.
Also ask about insurance-backed protection for the workmanship warranty. Product and workmanship cover are different, so a long panel warranty does not answer questions about the installation itself.
9. Cancellation rights
Read the cancellation section before signing. It should explain how to cancel, where to send the notice and what happens to any money already paid. Keep a copy of the signed quotation, contract and cancellation information.
If anything is unclear, ask the installer to put the answer in writing before you commit. This guide does not replace the terms of the actual contract or legal advice.
10. Payment schedule
The quote should show the total price and each payment stage. Check what event makes each payment due, which payment methods are accepted and whether the final payment comes before or after commissioning and handover documents.
A clear schedule lets you compare quotes fairly. One installer may show a low initial figure but leave later charges vague, while another may include the complete scope in one transparent total.
11. Export tariff and SEG help
Ask what handover information you will receive for arranging a Smart Export Guarantee tariff and whether the installer helps explain the process. Do not treat an export-income illustration as guaranteed.
The quote should make clear that the installer is supplying the system, not fixing a future export rate. Check current tariff terms separately when the installation is ready.
12. Get at least three quotes
Get at least three written quotations where possible. Give each installer the same information and ask the same questions so you can compare system size, equipment, expected generation, included work, warranties, deposit and payment stages.
Use PowerGuardian's screening bands as one part of that comparison. For solar, the shared bands run from unusually low below £1,200 per kWp through to high above £2,500 per kWp. For batteries, they run from unusually low below £300 per usable kWh through to high above £900 per usable kWh.
Final check before signing
Confirm that the total reflects the zero rate of VAT on qualifying residential solar panels and batteries, which runs until 31 March 2027. Then check that every promise which matters to you appears in the written quotation or contract.
Run the figures through the quote checker. It will not approve the installer or value the property; it will calculate a comparable unit price, identify the screening band and give you questions tailored to that result.
Sources and benchmark notes
Benchmarks last reviewed: Sept 2026. The zero rate of VAT on qualifying residential solar panels and batteries runs until 31 March 2027.
Frequently asked questions
Related solar quote guides
Screen your solar or battery quote against the same published-cost benchmarks used in this guide.
Check your quote in 2 minutes