

The staff at the shop I use the most did not know. But the self-service printers are different than the printers used by the staff. They might know for the printers they use, which is naturally more costly.
Creating something with symbols going all the way to edge seems like a good idea. I would not want any spacing between the symbols though, so I guess it would be non-trivial code.
Thanks. I’ll have a look at some of those approaches.
(edit) I used a feature in the KOMAscript pkg to produce circles that reach the edge of the paper. I also used one of the approaches in your link to create a frame at the point where the /expected/ boundary is, so that if the frame has any missing lines it would indicate where the specs may be wrong. But I must say I don’t trust LaTeX to produce an accurate frame because some lines are closer to the edge than others even though I asked for 4.2mm on all sides.