How this home value worksheet works

This calculator uses a small comparable-sales model. Each sale price is first moved forward to the valuation date using the annual market-movement scenario and the number of months entered. A direct feature adjustment is then added. The three adjusted sale indications form a low-to-high range and an evidence-weighted centre.

The method is deliberately visible. It does not claim to be an automated valuation model, and it receives no property address, title, geospatial, listing, planning, hazard or market data. You select the evidence and quantify differences. That makes the reasoning auditable but also places responsibility for the inputs on the user.

For a positive market-movement assumption, an older sale is increased to the value date. A negative assumption decreases it. A single annual percentage cannot reproduce month-by-month changes or a turning market. Use local evidence around both the sale date and value date, and test a range of movement assumptions when conditions are uncertain.

The feature adjustment uses the subject property’s perspective. Enter a positive amount when the subject is superior to the comparable, and a negative amount when it is inferior. For example, if the comparable has a substantially renovated kitchen and the subject does not, the subject adjustment may be negative. Document the reason and evidence for every adjustment.

Select comparable sales, not merely nearby prices

Strong evidence is usually recent, arm’s-length and physically comparable. Match property type first: a detached house, townhouse, villa and strata apartment can respond differently even in the same suburb. For apartments, consider building age, floor, lift, parking, aspect, view, internal area, outdoor space, facilities, strata condition and levies. For houses, compare land area and shape, frontage, slope, zoning, improvement size, layout, age, condition and development potential.

Location is finer than suburb. School catchments, traffic, aircraft noise, flood exposure, bushfire risk, views, walkability, public transport and proximity to commercial or industrial uses may affect buyer demand. Two properties separated by one road or planning boundary can have different markets.

Sale conditions matter. Check whether a transfer was between related parties, part of a development site, affected by a lease, sold off-market, bundled with another interest or subject to unusual terms. A distressed or non-arm’s-length transfer may not demonstrate ordinary market behaviour. Confirm that the amount and date represent the relevant settled sale information.

The NSW Valuer General’s public guidance for land-value objections illustrates the evidence principle: comparable sales should have similar features, and users should explain differences in matters such as area, view and location. It also warns that comparing a property only with median or average land values is not adequate evidence for an individual land value. Although this calculator concerns a whole-property scenario, the same discipline is useful.

Build feature adjustments without double counting

Create a comparison grid before entering a dollar adjustment. List land area, building area, bedrooms, bathrooms, parking, age, renovation, condition, orientation, outdoor space, view, topography, zoning and notable defects. Mark whether the subject is superior, similar or inferior to each sale.

Use market evidence to quantify differences where possible. A renovation’s construction cost does not automatically equal its contribution to sale price. A pool can add, subtract or have little effect depending on the buyer group, climate, site and condition. An extra bedroom created by an impractical layout may not have the same value as a genuinely comparable additional room.

Avoid double counting. If the sale price difference already reflects a larger land parcel and you enter a combined feature adjustment, do not add a second full land adjustment without analysis. Similarly, location, view and floor level can overlap. Preserve a note that shows the components and the final net figure.

Weight the closest evidence most highly, not the sale that produces the preferred answer. A five should represent a strong match and credible sale. A low weight can recognise a useful but imperfect sale, but it should not rescue an observation from a different market. Recalculate after excluding the weakest comparable; a large change is a warning that the estimate needs more evidence.

Do not confuse four different property values

An online price estimate can also differ from all four. An automated model may use broad sales data and property attributes, but it may not observe condition, unapproved works, views, defects or a recent renovation. Read its confidence range and data date rather than focusing on the centre number.

A council rates notice or state land valuation is not a shortcut to the current sale value of the improved property. Conversely, a high recent purchase price does not by itself prove the statutory land value is wrong. Use the objection and review process for the relevant jurisdiction when disputing a government valuation.

For family law, deceased estates, related-party transfers, capital gains tax, stamp duty, financial reporting or litigation, the required valuation date and legal test can be decisive. A current household estimate cannot simply be moved backward to a historic date. Engage an appropriately qualified valuer and adviser for the required purpose.

Interpret value, net proceeds and equity separately

The weighted value is a central scenario before selling costs and debt. The net-proceeds scenario subtracts only the costs entered. It does not calculate agent commission tiers, marketing, auction, conveyancing, repairs, discharge fees, moving costs, taxes or settlement adjustments. Prepare a transaction-specific budget.

The equity scenario subtracts the current loan balance from value without selling costs. It is not available cash and not necessarily the amount a bank will lend. A lender considers its valuation, loan-to-value ratio, serviceability, product rules and existing security. Ask the lender for a payout or lending assessment rather than treating calculated equity as an approval.

The spread is a measure of disagreement between three adjusted indications. Report it alongside the centre. If the spread is large, revisit comparability, market movement and feature adjustments. If it is small, still test data independence and sale conditions.

Round the conclusion to a level supported by the evidence. A result such as $987,436 can look precise despite uncertain inputs. A range or rounded figure usually communicates the model more honestly. Record the valuation date because property markets and available evidence change.

A careful pre-sale or purchase process

Inspect the subject property and verify title, planning, approvals, easements, strata records, building condition and hazards with the appropriate professionals. A price worksheet cannot identify structural issues, contamination, cladding, water ingress, termites, unapproved work or legal restrictions.

For a sale, request more than one agent proposal and ask each agent to identify the sales evidence behind the recommended range. Understand the marketing method, fees, commission, estimated expenses and agency agreement. An agent appraisal is not automatically an independent formal valuation.

For a purchase, compare the contract and disclosure material with the advertised property and obtain conveyancing or legal advice. Arrange building, pest, strata or specialist inspections as relevant. Confirm finance conditions and do not let an online estimate replace a borrowing buffer.

Update the comparable set immediately before an auction, offer or listing. Add newly settled sales when available, but distinguish contract date from settlement and publication lag. Save screenshots or official sale records with the date and source. The result should evolve with evidence rather than remain anchored to the first desired number.