How our estimates work.
We want the numbers to be helpful, not magically precise.
What a cost estimate means
Some pages begin with dated, third-party Australian cost-guide ranges. We link those sources beside the calculator. These ranges describe a particular scope and may not represent your quote, city, access conditions or product choice.
Other projects start without a benchmark price. That's intentional: when we don't have a defensible source, we ask you to enter your own estimates rather than generating a misleading figure.
Calculations
For most projects, the per-unit low and high ranges are multiplied by your selected quantity. Where a sourced first-unit and incremental-unit pricing model is available (currently power points), the first-unit rate is applied once, and an additional-item rate is applied to the remaining units. Additional one-off costs are added once, then the optional contingency percentage is applied to the subtotal. A manual custom quote can replace the published reference rate. Calculators do not account for rebates, regional multipliers or prices from live merchants.
What can change a quote
Site access, materials, labour scheduling, disposal, approvals, hidden defects and GST treatment can materially change the cost. Ask providers to itemise these matters in writing.
Sources and review cycle
The original seven starter ranges were checked on 28 October 2026. Three regional supplier benchmarks were added on 12 November 2026. The medium scenario is the midpoint unless a published option or your own rate is entered. This confirms the published reference and scope, not the price at an individual property. GST remains unconfirmed where the source does not state it. Other worksheets use your own inputs. The wardrobe guide links a product benchmark but deliberately leaves the all-in calculator blank. Every source-backed calculator identifies its origin. We aim to review commonly used cost assumptions periodically, but you should always verify current pricing independently.
Safety and licensing
Electrical, gas, refrigeration, plumbing, building and waterproofing work can require appropriately licensed or qualified tradespeople. Regulations vary by Australian jurisdiction. Our website does not instruct you to perform work for which licensing is required.
Commercial independence
At initial launch, the website contains no paid rankings, live installer connections or affiliate arrangements. If partnerships or advertisements are introduced, they must be clearly disclosed and should not alter the underlying numerical calculations.