Choosing the right builder for your home renovation or extension is one of the most important decisions you’ll make. Get it right, and you’ll have a seamless experience that adds value to your home. Get it wrong, and you could be left with delays, cost blowouts, and a half-finished project—or worse, one riddled with defects.
Cowboy builders operate on the fringes of the industry, cutting corners, disappearing when things go wrong, and leaving homeowners out of pocket. So how do you spot one before it’s too late?
1. They Haven’t Operated Under the Same ABN for More Than 10 Years
A reputable builder stands the test of time. If a company keeps changing its business name or Australian Business Number (ABN), that’s a major red flag. This could indicate past insolvencies, disputes, or dodging warranty claims.
It’s also important to remember that an experienced builder who has started their own business isn’t necessarily a safe bet either. They might have been a great builder for many years within a well-run company, but that doesn’t mean they can successfully run a financially stable business themselves. You need certainty that your builder isn’t just skilled on-site but also has the financial strength to complete your project without cutting corners or running into trouble.
👉 Fact: More than 80% of construction businesses don’t survive beyond five years and a further 50% of those that do survive, close in the following five years. If a builder has been operating under the current ABN for less than a decade, beware.
2. They Ask for a Deposit Over 6.5%
In Western Australia, builders legally cannot ask for more than 6.5% of the contract value as a deposit before work begins. If they’re requesting 10%, 20%, or more—walk away.
👉 Why it’s risky: Overcharging deposits is a common tactic used by underfunded builders who rely on incoming cash to prop up old projects.
3. They Don’t Have Genuine Google Reviews from Real Clients
A reputable builder should have a history of authentic client testimonials. If a builder has:
✅ No Google reviews, or very few
✅ Only five-star reviews that sound generic
✅ No detailed project images attached to reviews
Then proceed with caution. Real clients provide real feedback. Check out the testimonial from past Addstyle clients via Google or here.
4. Their Website Uses Stock Photos Instead of Actual Projects
If a builder claims to be experienced but their website is filled with generic stock images instead of real completed projects, alarm bells should ring.
👉 Pro tip: Do a reverse Google search on photographs of their projects from their website.
5. They Invoice for a Deposit Before Providing a Housing Indemnity Certificate
Before paying a cent, your builder must provide a Home Indemnity Insurance (HII) certificate in your name and address. This insurance protects you if the builder goes bust mid-project.
👉 No certificate? No payment. Any builder who tries to sidestep this process is operating outside the law.
6. They Give You a “Quote” Instead of a Proper Specification & Fixed-Price Contract
A vague “quote” means nothing. A professional builder provides:
✅ A detailed specification, outlining every material and inclusion
✅ A fixed-price contract, so you know exactly what you’re paying
🚨 🚨 Beware of builders who provide a lump sum price without a detailed specification. This is a classic sign they plan to hit you with variations later.
7. They Ask You to Become an Owner-Builder
If a builder suggests you take out the building permit in your own name, it means they’re avoiding responsibility. This transfers all liability onto you—if something goes wrong, you have no legal protection.
👉 Fact: A professional builder should always take out the permit in their name. If they ask you to do it, they are either unlicensed or dodging regulations.
8. They offer a Too-Good-To-Be-True Price
Rogue builders often try to tempt you into signing by:
❌ Offering “limited-time” discounts
❌ Claiming they can “start next week” (most reputable builders have a waitlist)
❌ Providing a price that seems far lower than competitors
👉 Why it’s a problem: Low quotes usually mean hidden costs, cheap materials, underpaid trades, or lack of inclusions—none of which lead to a quality renovation.
9. They Don’t Have Industry Recognition or Awards
Legitimate builders stand behind their work and have:
✅ A track-record of Industry awards (HIA, MBA, or other reputable organisations)
✅ Active memberships with builder associations
✅ A consistent project history
🚨 If a builder has zero professional recognition or isn’t affiliated with industry bodies, it’s worth asking why.
What a Reputable Builder Looks Like
While it’s important to recognise the warning signs, it’s just as valuable to know what a quality, trustworthy builder looks like. A professional renovation and extension specialist will:
✅ Have a long-standing, stable business history under the same entity and licensing.
✅ Provide a lump sum, fixed-price contract with a clear and detailed specification for full transparency.
✅ Hold all necessary licences and insurance before requesting any deposit payments.
✅ Showcase their past work through a strong portfolio of completed projects.
✅ Have a track record of positive client experiences, backed by genuine testimonials and reviews.
✅ Offer clear communication and realistic timelines, without pressuring you to sign quickly.
Choosing the right builder is about more than just price—it’s about peace of mind, quality craftsmanship, and a smooth, stress-free renovation experience.
By doing your due diligence and selecting a builder with a proven reputation, clear processes, and a commitment to quality, you’ll ensure your home transformation is in the safest of hands.
To assist homeowners in their search for a renovation builder, we have compiled an easy to follow guide which provides warning signs to look out for, questions to ask and some surprising red flags to look out for. You can download it for free here.
A quality home renovation is a major investment. Make sure you’re putting it in the right hands.
