We are four well traveled middle aged women who will be in Berlin for just one day, because of airport connections. We want to find a local guide to get the most our of our short stay. We did this in Belfast and was one of the best parts of my month in Ireland!
Strongly recommend getting in touch with "Jeremy, the Berlin Expert". He does the best tours of Berlin, with a very personal touch.
We took a 'free' Starbucks walking tour in Berlin. Most Starbucks coffee places in Germany have info cards.
Our tour met outside the Starbucks near the Brandenburg Gate. Our guide was a history student from England - very
knowledgable in German/Berlin history. The walking tour lasted 3 hours with a 30 min break in a small restaurant near Checkpoint Charlie. At the end of the tour, he'll ask you for a contribution whatever you want to pay. Some alreay
had left our group (of about 15 people) without paying anything - therefore 'free'.
There are dozens of high quality, professional tours and tours guides in Berlin. These are far better than a scripted "free" tour. They will all have guides that you can book for a private tour. Check Trip Advisor to read the reviews. See what Rick has to say about the various tours too.
A couple of years ago, he had a blog post where many of the free tours shady business practices were revealed. Many of which are illegal.
If 15 people left your tour without tipping, this guide must not have been very good, and was probably also crying after you all left. These Free tour guides have to pay their company about 2.50-3 euro for every person that begins their tour. If it is expected to tip, then they aren't really free either.