Woodstock音乐节——求助从Berlin到波兰Kostrzyn nad

在柏林的朋友，我想请问一下怎么买从柏林到Kostrzyn nad Odrą的票，我看到网上说
“DIRECTIONS FROM BERLIN Schoenefeld AIRPORT:
Get a Berlin BC one way ticket - take tram (S9) to Ostkreuz - change to S5 or S7 - take two stops to Berlin Lichtenberg - get/join Berlin-Brandenburg ticket (group ticket for 5 ppl) - take Oderlandbahn (RB26) to Kostrzyn !!”

但是我看到价格怎么试25欧？不是应该5块钱吗？Group ticket我也不懂怎么运行~

谢谢！