Budget: 4,95 for the wallpaper, 7,35 for paste and brush.
Schedule: 3 hours incl. waiting for paste.

Lessons learned:
Some workpackages (pieces of wallpaper) may appear not too big, but once you are in work process (and the paper is soaked and squashy), you start to curse because you did underestimate the needed effort (and the number of needed arms…)
Never ever do such work alone.
If you do it alone, love and accept the result.
Enjoy the silence.