The villain is not the door-knocker, it is the quote with one number and nothing behind it: no load calc, a system sized to the rebate, no switchboard check, no CoC. The red flags in order, plus the five-minute routine to verify a renewables or electrical quote before you sign.
The cheap energy quote has one trick: a single attractive number with nothing behind it. No load calc, no named parts, no switchboard check, no Certificate of Compliance. It wins on price because it leaves off the work that costs money to do properly. This guide names the red flags in order and gives you a five-minute routine to verify any solar, battery, EV or commercial quote before you sign.
The villain: one number, nothing behind it
A quote that is just a price and a product name is hiding its omissions inside the headline. The low number is not the product of efficiency; it is the product of leaving things out. The skill is not finding the cheapest quote. It is finding which quote is cheap because it is genuinely lean, and which is cheap because three lines are missing.
Red flags, in order
These are ranked by how much they cost you when they turn out to be true. The first three are where most of the money and most of the risk hide.
No load calc. The system size was picked, not derived, which usually means it was sized to the rebate.
No switchboard check. The board was never inspected, so an upgrade is either skipped or coming as a mid-job surprise.
No Certificate of Compliance mentioned. The compliance paperwork is unaccounted for, which is the part that protects you legally.
Unnamed hardware. "Tier 1 panels" and "premium inverter" instead of make and model, so a cheaper unit can be swapped in.
Rebate as a vague reduction. "Government rebate applied" with no dollar figure, so you cannot tell how much reached you.
We show you the load calc, the cable sizing and the CEC and compliance paperwork before you sign. The cheap quote leaves all three off and competes on the number that is left.
The five-minute verification routine
Before you compare any two quotes on price, run each through the same five checks. It takes about five minutes and it reorders most shortlists.
Load calc? Is there a consumption analysis and a system size derived from it.
Named hardware? Are the panels, inverter or charger named by make and model.
Switchboard check? Does the quote state your board's condition and price any upgrade as a line.
Rebate as a figure? Is the STC or incentive shown in dollars, not as a vague reduction.
CoC promised? Is a Certificate of Compliance part of the deliverables.
A quote that passes all five is comparable. A quote that fails three is not cheaper, it is smaller, and the gap is the work it left off. For the full anatomy of a good quote, see what a solar quote should include, and for the board specifically, what triggers a switchboard upgrade.
Then, and only then, compare on price
Cheap is not the enemy. A genuinely efficient installer can be thorough and competitive at once. The enemy is comparing a complete quote against an incomplete one as if they were the same job. Once every quote passes the five checks, the cheapest one that still shows the load calc, the named hardware, the board check, the rebate figure and the CoC is the right one. That is comparing like for like, and it is the only comparison worth making.
The cheap energy quote relies on you reading only the number. Read the five lines behind it instead, and the real price, including the parts the cheap quote left off, comes into view before you sign rather than after.
Common questions
What is the single biggest red flag in an energy quote?
One number with nothing behind it: no load calc, no named hardware, no switchboard check and no Certificate of Compliance mentioned. The reason it is the worst sign is that every omission is a corner cut that you pay for later. Next step: ask for the quote itemised, and treat any line they cannot produce as a line they planned to skip.
How can I check a quote in five minutes?
Run five checks: is there a load calc, is the hardware named by make and model, is the switchboard checked, is the rebate shown as a figure, and is a Certificate of Compliance promised. The reason this works is that a cheap quote fails most of them quickly. Next step: hold the quote against these five points before you compare it on price.
Why is "sized to the rebate" a problem?
Because the system gets sized to maximise the incentive rather than to match how you use power, which wastes money on capacity you do not need. The reason it happens is that the rebate scales with system size, so a bigger sale earns a bigger discount and margin. Next step: ask to see the consumption analysis that justifies the size quoted.
Is the cheapest quote ever the right one?
It can be, but only when it passes the same five checks as the others. The reason cheap is not automatically wrong is that a genuinely efficient installer can be both thorough and competitive. Next step: compare like for like by itemising every quote, then pick the cheapest one that still shows the load calc, the hardware, the board check and the CoC.