Our methodology is designed to make home-project information understandable and auditable. We prefer transparent assumptions and ranges over false precision.
1. Define the project scope
Before discussing cost, we identify what the project actually includes. A roofing job, bathroom renovation or heating replacement can mean very different things depending on removal work, access, materials, permits, repairs to hidden damage and finish level.
2. Separate measurable inputs from market prices
Where possible, calculators use inputs the homeowner can verify: dimensions, waste percentage, watts, hours of use, tariff rate, quoted price or contingency. This reduces reliance on generic averages.
3. Treat prices as ranges
When price guidance is published, it should be presented as a planning range with the location and time period made clear. We avoid implying that a national average is a local contractor quote.
4. Distinguish USA, UK and Australia context
U.S., UK and Australian pages use the relevant currency, terminology and regulatory context. We do not create one market by simply converting another market’s currency.
5. Review the cost drivers
- Project size and measured quantity
- Material or equipment specification
- Property age and condition
- Access, height and complexity
- Removal, disposal and making-good work
- Permits, inspections and professional services
- Regional labour and supplier conditions
- Urgency and project scheduling
6. How the homepage repair estimator is built
The symptom-based estimator uses separate USA, UK and Australian planning ranges. Australian ranges are expressed in AUD and are calibrated to Australian category-level repair guidance rather than simple currency conversion. The ranges are synthesized from current published 2026 repair-cost guides and are intentionally broad where one symptom can have several possible causes. Reference sources used to benchmark the current dataset include Angi refrigerator repair data, Angi roof repair data, Angi window repair data, Checkatrade appliance repair data, Checkatrade washing-machine data, Checkatrade roof repair data, and HomeGuide drywall repair data. Australian calibration also uses 2026 national guides from hipages appliance repair, plumbing, electrical, roof repair, plaster repair, window repair and air-conditioning repair data. Symptom-level Australian figures are intentionally broad planning bands within those category benchmarks; they are not contractor quotes. A selected symptom is not a diagnosis, so the final contractor price can fall outside the displayed range.
7. Update when assumptions change
Pages should display a last-updated date when substantive content is revised. Major changes to calculation logic or data assumptions should be reflected in the article or methodology notes.
8. Keep professional boundaries clear
Cost information is not a substitute for inspection, engineering, electrical, gas, building-control, planning, legal or other professional advice. Safety-critical work should be assessed by an appropriately qualified professional.
How to use our figures
Use RepairCostPilot to prepare questions and a budget range. Then obtain written quotations that describe the same scope. If quotations differ significantly, compare inclusions and assumptions before comparing the total number.