Short answer：“Most expensive” can mean total price, price per area or affordability relative to income. Without aligned years, samples and definitions, a reliable global ranking cannot be assigned.
Align definitions
Separate cities from countries, new from existing homes, property types, area measures and currency dates. OECD notes cross-country definition problems; rebased index levels are not absolute price rankings.
Include living and holding costs
Household comparisons also need tax, finance, management, transport and income context. The old city table and ranking are withdrawn. A current ranking would require a new consistent dataset.
Before deciding
- Do not mix means and medians
- State periods and coverage
- Separate price from affordability
Sources and method
Sources support the specific rules described. Checklists and hypothetical calculations are editorial explanations, not measured market results or individual approvals.
Revision：Removed unsupported experience, case outcomes and statistics; corrected the topic-specific rules and limitations described above.
Scope：General information only, not personalised legal, tax, immigration, admissions or investment advice.