Cost per square metre
Cost per square metre is the quote total divided by the stated floor area. It compares two house quotes for similar size; it is not proof one price is fair.
Also called: cost per m², price per square metre
The figure only works when the total and the area describe the same scope. A quote that excludes the kitchen will show a lower cost per m² than one that includes it, even if the houses are the same size.
A regional index built from many quotes stores lines with place and date. A band appears only when enough records exist; a sparse city should say so rather than invent an average.
On a paid reading the model lists cost per m² and per ft² as hypotheses from your stated area. Free tools may read area from a plan or record place for the index without judging fairness.
Use the same area on every quote before you compare. Ask the contractor which area their m² uses if it differs from yours.