I think NSB-or VY now has stopped doing that-too much trouble for far too few people that also bring in only losses. The Swedes and Finns have too.

Again: Nordmenn_ check the overview of seewulf on howtodo most of REServ-if needed-by yourself on easier ways-mostly online and via mail. It differs a lot per country and even the need to do it also varies enormously. Most newtimers however all seem to want to do the very same routes-not very imaginative-and these these get clustered up in hi-season. Thats via FRance to ESpana.

Husk plassbillett-nu sta du der! that was printed in old Ruteboks that NO once had. IF you go all the way med taget-at least you need the DSB direct trains KObenhavn/Köpenhamn till Hamburg-or use locals with more changes.

Where is the mentioned “seewulf on howtodo”? Could you provide an URL?

This:

is what he was alluding to.

I read the guide.

I have a similar issue, though I come from Italy. The question is: okay, I can reserve seats on nightrains on the websites of the train companies, but aren’t they much more expensive than reserve them via app?

And, if we go in person to book those tickets, are discounts as passholders applied?

Thanks in advance!

Usually the other way around, since Interrail charge an extra 2€ booking fee per person and train and some reservations are much more expensive to begin with (e.g. for Germany or Austria).

Sure.