Comparable Sales Explained for Property Buyers
Comparable sales — often called "comps" — are recently sold properties used to estimate what a home is actually worth. Buyers and agents use them to check whether a listing price reflects the market or misses the mark.
What Does Comparable Sales Mean?
Comparable sales — often called "comps" — are recently sold properties that share similar features with the one you're looking to buy. Think location, land size, property type, condition, and number of bedrooms. When grouped together, they give a realistic picture of what buyers have actually paid for similar homes in the same area.
You'll typically encounter comparable sales when you're researching a property before making an offer, when you're trying to work out what to bid at auction, or when your bank conducts a formal valuation. Agents also reference them when setting a guide price, and solicitors sometimes use them in negotiations to test whether a price reflects the market.
The practical implication is this: comparable sales are the closest thing buyers have to an objective price check. They won't tell you what a property is worth to you personally, but they'll tell you what other buyers have recently decided to pay for something similar — and that's a useful anchor when you're trying to decide whether to make a move.
Why This Matters for Buyers
Without a reliable sense of what comparable properties have sold for, you're making offers with very little to anchor to. That can mean overpaying when the market is quiet, or setting your limit too low in a competitive segment and missing out. Comparable sales don't remove uncertainty entirely, but they reduce it — and that matters when significant money is on the line.
They also matter when it comes to finance. Your lender will instruct an independent valuation, and that valuer will use comparable sales to assess whether the agreed purchase price is supportable. If the comps don't justify the price, the bank may value the property lower than expected — which can affect how much you can borrow, or whether finance proceeds at all. Understanding what the comps are likely to show before you exchange gives you time to manage any gap.
In negotiations, comparable sales give you a factual basis for your position. If a vendor is asking significantly above what similar properties have sold for, you can make a lower offer with evidence rather than preference. Agents understand that buyers are referencing recent data, so a well-reasoned position grounded in comps tends to carry more weight than a bare number.
Finally, comparable sales matter beyond the purchase itself. They underpin your capital growth assumptions, your ability to refinance, and any future sale price. Buying in line with — or below — what the comps support is one of the more reliable ways to protect your equity position over time.
Common Mistakes Buyers Make
Comparable sales look straightforward, but buyers regularly misuse them in ways that lead to poor decisions. Here are the most common errors:
- Using comps that are too old — Property markets can shift over a matter of months. A sale from 12 to 18 months ago may not reflect current conditions, especially after interest rate changes or a change in local supply.
- Selecting properties that aren't genuinely comparable — A four-bedroom house on 800m² is not a reliable comp for a three-bedroom house on 450m², even if they're on the same street. Land size, aspect, condition, and number of bedrooms all affect what buyers pay.
- Cherry-picking comps that support the price they want — Confirmation bias is real. Buyers sometimes focus on sales that justify what they've already decided to offer rather than building an honest picture from all available evidence.
- Relying solely on the agent's comparables — A selling agent's primary obligation is to the vendor, not the buyer. Their selection of comps may be accurate, but it's worth verifying independently or having someone with no stake in the outcome review the same data.
- Not accounting for off-market sales — Some properties change hands without a public listing. Those sales may not appear in commonly used data platforms, which can leave gaps in the comparable sales picture — particularly in tightly held streets or estates where stock rarely comes up.
How This Shows Up in the Illawarra
The Illawarra property market is relatively segmented, which makes comparable sales both more important and more difficult to use well. Wollongong's inner suburbs behave differently from coastal Shellharbour or escarpment-fringe areas like Figtree or Farmborough Heights. Using a sale from a nearby suburb as a direct comparable can produce a misleading result if the underlying drivers of that price — sea views, proximity to the CBD, school catchment — don't apply to the property you're buying.
In suburbs with limited stock — particularly along the Northern Illawarra coast where property types are diverse and turnover is low — comparable sales can be sparse. When few homes of a particular type trade each year, two or three sales effectively become the entire benchmark for that segment. In those situations, buyers need to weight recent sales heavily and adjust carefully for condition, since a single well-presented renovation selling above its neighbours can skew the picture if taken at face value.
In parts of central Wollongong and Shellharbour where strata and townhouse stock is more abundant, comparable sales data is generally more reliable and easier to interpret. There's enough transaction volume to draw meaningful conclusions across price points and building types. For buyers targeting houses in smaller pockets or niche coastal markets, working with someone who knows the local market and has access to a full sold-price dataset is often more useful than trying to interpret regional averages from public listing platforms.
Practical Takeaway
Before making an offer or setting an auction limit, gather at least three to five genuinely comparable sales from the past three to six months. Focus on properties that match the key variables: property type, land size for houses, condition and presentation, location within the suburb, and bedroom and bathroom count. If you can't find enough direct comps in the immediate area, widen your search slightly and adjust for any meaningful location difference.
When you review them, look at the range rather than trying to arrive at a single number. Comparable sales rarely all land at the same figure — the spread between the lowest and highest tells you something about how much condition, presentation, and individual buyer motivation are influencing results. Your target property should sit somewhere in that range, adjusted for how it compares in quality and appeal to the sold examples.
If you're unsure how to read the data, or you're buying in a market where comparable sales are sparse or hard to interpret, that's exactly the kind of analysis a buyers agent can handle for you. Having someone assess the comps without any interest in the outcome is one of the clearer ways to avoid paying above what the evidence supports.
Frequently Asked Questions
What are comparable sales in property?
Comparable sales are recently sold properties that share similar characteristics with the home you're considering buying. They're used to assess whether the asking price is in line with what buyers have actually paid for similar homes in the same area.
When do I use comparable sales?
You use them before making an offer, when setting an auction limit, or when negotiating price. Your lender's valuer will also use comparable sales when determining whether your agreed purchase price is supportable for finance purposes.
Are comparable sales risky to rely on?
They're not risky if used carefully, but they can mislead you if the sales you're using are too old, too different, or too few. The more genuinely comparable and recent the sales, the more reliable the picture they provide.
Can I negotiate using comparable sales?
Yes. If the comparable sales data suggests a property is priced above where similar homes have been trading, you have a factual basis for a lower offer. Agents and vendors understand that buyers reference recent data, so a well-reasoned offer grounded in comps is a credible starting position.
Should first home buyers look at comparable sales?
Absolutely. First home buyers are especially at risk of overpaying because they haven't yet built up experience reading price signals in a market. Reviewing comparable sales before making any offer is one of the most practical steps a first home buyer can take.
How recent should comparable sales be?
Sales from the past three to six months are most reliable. Markets can shift with interest rate movements or changes in local supply, so older sales should be used with caution and weighted less heavily when forming your view.
How do comparable sales relate to the NSW buying process?
There's no formal requirement to review comparable sales in NSW — it's something buyers do as part of their own due diligence. However, your bank's valuer will carry out their own comparable sales assessment before approving the loan, so understanding what they're likely to find before you exchange is a useful step.
Does a buyers agent help with comparable sales?
Yes. Interpreting comparable sales objectively is one of the core things a buyers agent does. They typically have access to sold price data that isn't fully visible on public platforms, and they can identify which sales are genuinely comparable rather than just superficially similar.
If you'd like help interpreting comparable sales before making an offer, we're happy to walk through the data with you. Reach out through our contact page.
