New bathroom walls double-tiled

For a 7.5 m2 bathroom, what would be a reasonable discount? If we insisted on doing it new, sanitary fixtures would have to be dismantled, tiles and drywall removed, drywall (2nd layer) renewed, retiling, sanitary fixtures reinstalled Would have to be done

The question is whether you could insist on that? On what basis? The proportionality would definitely not be given, as you have no disadvantage. 1 cm is nothing, you have that tolerance with plaster and masonry. So if it is now done cleanly, I would demand a small discount and that’s it (1000 euros?).

On what basis do you want a discount? What was not built as ordered?

Walls: are there
Tiles: are there
Grout: was done

Discount? €0

On what basis do you want a discount? What was not built as ordered?

Walls: are there
Tiles: are there
Grout: was done

Discount? €0

That's how it is. And regarding the measurements: they are all just rough construction measurements that are stated - black on white.