Right, it should be higher than you expect but it shouldn't be too high. If you expect €100 and ask for 20% more it should be safe if the company is willing to

Right, it should be higher than you expect but it shouldn't be too high. If you expect €100 and ask for 20% more it should be safe if the company is willing to pay €80. If they aren't it's probably too much of a mismatch in expectations to make everybody happy. But a candidate can only do this well if they know the market to within 20%, which might take a fair bit of research and asking around.