Energy

Before You Sign That Solar Quote

Published 13 July 2026 · Osborn Energy Advisory

I've sat across from well over 600 households and businesses working through energy decisions over the past nine years, and reviewed more solar and battery quotes than I can count. The mistakes I see aren't rare or exotic. They're the same handful of issues, over and over, dressed up in different paperwork.

Here's the thing nobody tells you when you're staring at a solar quote on your kitchen table: the quote that looks the most impressive on paper is often the one doing you the least favours.

The pattern I see again and again

Solar and battery quotes are built to be compared on price and headline numbers — system size, panel count, battery capacity. What they're not built to be compared on is whether any of that actually matches your house, your usage, and your goals.

The patterns that cost people the most, in rough order of how often I see them:

  1. Oversized systems. Bigger isn't better if you can't use or export what you generate. An oversized system inflates the upfront cost without proportionally improving the payback.
  2. Battery sizing that doesn't match usage. A battery sized for someone else's household — not yours — is one of the most common ways people overpay for storage they can't fully use.
  3. Inverter and panel mismatches. Getting the inverter capacity wrong relative to the panel array either wastes generation capacity or creates compliance issues down the track.
  4. Attachment and mounting shortcuts. How a system is physically attached matters more than most quotes let on — and it's the detail most easily skipped when a quote is rushed.
  5. No real comparison to your actual usage data. A quote built on assumptions instead of your actual bills is a quote built on guesswork.

Why "get three quotes" isn't quite right

The standard advice is to get three quotes and compare. It's not bad advice, but it misses the point: three quotes built on the same flawed assumptions will just agree with each other. Comparing three oversized systems doesn't tell you the system should have been smaller.

What actually helps is someone who isn't selling you anything looking at the quote against your real usage — not another quote trying to win your business.

What a proper review actually catches

In the last 16 months, 96% of the people I've worked with avoided overpaying for a battery they didn't need — not because bigger sells better, but because getting the sizing right the first time is what makes the payback numbers real instead of aspirational.

That's not a coincidence. It's what happens when someone reviews the quote against your actual data instead of a sales script.

If you want to make sure your quote isn't part of the other 4%, get an independent second opinion before you sign anything — that's exactly what a Solar & Battery Clarity Session is for.

The questions worth asking before you sign

If you're not getting an independent review, at minimum ask your installer these:

If any of those get a vague answer, that's worth pausing on.

The real cost of getting it wrong

Nobody regrets asking one more question before they sign. Plenty of people regret the system sitting on their roof three years later that never quite paid back the way the quote promised. The gap between those two outcomes is usually a single, independent review — cheaper than the mistake it prevents.

FAQ

Is a solar quote review worth it if I've already got three quotes?

Yes — three quotes compared against each other still won't tell you if all three share the same sizing mistake. A review compares the quote against your actual usage, not against other quotes.

How long does a solar quote review take?

Most reviews are turned around quickly once we have your quote and recent usage data — no lengthy back-and-forth required.

Do you sell solar systems or install anything?

No. The value of an independent review is that there's nothing being sold — the assessment is based on what's right for your situation, not what earns a commission.

What information do I need to provide for a review?

Your quote (or quotes) and, ideally, your recent electricity usage or bills, so the sizing can be checked against real data rather than assumptions.

Is this only for people who haven't signed yet?

It's most valuable before you sign, but if something feels off after installation, it's still worth a conversation.

Don't let guesswork decide a 10-year investment.

Jarrod Osborn has spent 9+ years in the South Australian solar and battery industry. Osborn Energy Advisory is independent — no installer commissions, no agenda.