We won't rent a car. Trying to find some info of the train transportation for:
Munich to Prague
Prague to Berlin
Berlin to Cologne
Cologne to Frankfurt
Done some research and find some of them also have passes for certain days use. Which one is better for the above transportations: DB (ICE), Raileurope.com, Eurail.com etc. I heard 49 euro pass only for people who have Germany banking account to be able to buy it.
Have a look at
https://www.seat61.com
A well regarded site for train info.
You don’t need Rail Europe. Download the Deutsche Bahn app & have fun planning!
Köln (Cologne in German) to Frankfurt is a quick ride — about 1 hour, 20 minutes.
I always buy our Germany train trips on intercity or Eurocity trains in advance on bahn.de, and have never used any kind of “pass”. For longer trips such as you contemplate, especially the cross-border trip to Prague, there can be significant discounts for advance purchase.
But maybe there is a better way, and one of the experts like Lee will see your question and provide a definitive answer.,