In our house, we had someone revive the existing floor in the entire basement, except for the bathroom and laundry room, as it was framed with wood beams. In some sections, some concrete had to be chipped away to ensure it was even. It cost a little over 100' including the installation of new parquet. The area was maybe 60-70 sqm?
If it’s the same against the walls, I don't know. Presumably, it should be cheaper since you're not buying parquet for X00/square meter.