It’s natural to want the best price, and solar quotes can vary a lot — so a rock-bottom number is tempting. But solar is one of those purchases where the cheapest option frequently turns out to be the most expensive over time. That’s not a sales line to push you toward premium gear; it’s the genuine economics of a system that’s meant to last 25 years. Here’s exactly how a cheap install quietly costs you more, so you can tell a good deal from a false one.
A 25-year asset rewards quality
The core reason is the timeframe. Solar isn’t a disposable purchase — it’s a system you’ll rely on for two-plus decades. Over that long life, small quality differences compound enormously. A component that’s slightly cheaper but fails years earlier, or generates a little less every single day, adds up to far more than you saved at purchase. Cheap solar saves you money once, up front; quality solar saves you money every year for 25 years.
Where a cheap quote cuts corners
A suspiciously low price has to come from somewhere. Usually it’s one or more of these:
- Budget panels. Cheaper, lesser-known panels may degrade faster (losing more output each year) or come from a maker that won’t be around to honour a warranty. You generate less, for fewer years.
- A short-lived inverter. The inverter is a favourite place to save, because buyers don’t scrutinise it. A budget inverter may fail sooner, bringing forward that $1,500–$3,000 replacement — sometimes more than once.
- A rushed or under-spec’d install. Cutting labour means less care with mounting (leaks or lifting), wiring, and the safety components like DC isolators. Poor installation is a leading cause of real-world faults and even fires.
- Things “left out” of the quote. Scaffolding, a needed switchboard upgrade, or proper isolators omitted to hit a headline price — costs that reappear later, or safety corners you don’t want cut.
- A thin or worthless warranty. A cheap installer offering a long warranty means little if they’re not around in five years to honour it.
How it surfaces later
The trouble with these savings is that they’re invisible at purchase and expensive afterwards. They show up as:
- Lost output — a system quietly generating less than it should, every day, eroding your savings.
- Early replacements — an inverter (or panels) failing years sooner than they should.
- Warranty headaches — claims that can’t be made because the brand or installer has vanished.
- Safety problems — the worst case, where a corner cut on isolators or wiring becomes a hazard.
By the time these appear, the upfront saving is long gone and you’re paying to put things right.
What “good value” actually looks like
The answer isn’t “always buy the most expensive”. It’s to judge on value over the system’s life, not the sticker price:
- A reputable panel and inverter with solid, claimable warranties.
- A registered, accredited installer with a workmanship warranty.
- An itemised quote with nothing important left out.
- A price in the normal band (roughly $2,000–$2,500 per kW for grid-tied) — not the lowest, not the highest.
A quote dramatically below the others isn’t a bargain to grab; it’s a prompt to ask what’s been sacrificed.
The verdict
Cheap solar can cost more because it’s a 25-year asset where corners cut up front — budget panels, a short-lived inverter, a rushed install, omitted essentials, a hollow warranty — resurface as lost output, early replacements, warranty headaches, and sometimes safety risks. The saving is one-off; the costs recur for decades. Judge a quote on whole-of-life value, insist on quality components and a proper installer, and treat a rock-bottom price as a red flag rather than a win.
Get a free assessment for an honest read on what good value looks like for your home.
Sources: Component lifespan, install-quality, and pricing-band guidance per NZ industry references (2026). Figures vary by home and installer.