<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by JohnG:
Yes, you tip. Most definitely.
Cash, the harder the request, the bigger the tip, for your request a 20 Euro note should be about right, certainly not less.
This topic has come up before, a search should yield further info.
Enjoy your trip to Berlin, a great city. 
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20 Euros seems like quite a bit to me for a rather simple service, but I guess it really depends on the hotel and the circumstances.
Oh, and Bayern München will most definitely win the title again
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