Sylvain VAN DER WALDE wrote:
P.S. I've just changed the partition beads, and the two inner cords on a
small sash window. I wonder how much I would have been charged for this by a
professional person?

Partition beads... parting bead? Anyway, well done - this is the sort
of thing that many people would have DIY'd a while ago. Now I hear
that sometimes people change the whole window 'cos a cord has broken!