The theory test is in German but I beleive you can request an English version. In any case, the trick with the test is that they will ask you I think 60 questions from a pool of 140 questions, and most of the questions involve choosing the correct situational picture/signs. So if you've got the 140 questions memorized, it should not be a problem. Your boat school will sort this out for you.

You will probably need about 10-15 hours of lessons at Fr.100 per hour. For the test itself, you need to rent the boat for another 1-2 hours, depending on how far you are from the testing center.