There is also a risk of reporting two genuinely different units as duplicates. Include the shared evidence and the uncertainty rather than making a stronger claim.
I’m based in Vancouver, Canada, and used SeLoger while searching for a detached home around Edinburgh. The coverage was useful, and price per square metre helped with initial comparisons, but duplicate adverts, stale availability and inconsistent floor-area fields made the shortlist less...
You could post one anonymised example in the relevant local board: asking price, property type, general area, condition, likely renovation and the completed sales you think are comparable. Members can then challenge the comparison itself instead of debating abstract averages.