I am using the Italian and German sites to look up overnight train schedules from Florence to Munich and from Munich to Amsterdam. The fares shown are upwards of 100 Euro. Will this really be how much it costs if purchased in the train station a few days ahead of time? We are not buying in advance and are ok with the fact we may not get sleepers.
Do you truly need to be flexible with your travel times? Popular night trains often sell out weeks in advance. Not only will you pay a high fare if you wait until a few days before departure to buy your tickets, you may be out of luck completely.
If you can, book in advance, get a discount fare, and get peace of mind--all in one deal.