Thanks for all the the tips given! We had a wonderful time in Switzerland and I must say that the Alps were absolutely incredible to see and explore for two weeks! As planned, we drove around Switzerland and also shortly visited Liechtenstein, Austria, Italy, France and Southern-Germany.
I managed to get notes from all of these countries! In Switzerland and Liechtenstein my strategy was to exchange one

, 100€ into CHF and 100€ back in

. This request was granted everywhere, so in total I managed to get 83 notes in

Switzerland and 50 notes in

Liechtenstein. I find these numbers a success, although I found no hits.
It was relatively easy to receive small euros in every part of Switzerland, but often one needed to pay 5CHF fee for the transactions. In Liechtenstein I visited Liechtensteinische Landesbank, which didn't take any fee, but the exchange rate was a bit worse there.
We also visited Austria (Feldkirch), Italy (Courmayeur) and Southern-Germany (Lörrach, Weil am Rhein) shortly during our stay and in all of these countries I had absolutely no problems exchanging money! The service was just superb in every bank and I didn't need to pay any fees. In France swapping euros wasn't that easy, but believe it or not, I managed to change money twice in a French bank! In Chamonix-Mont-Blanc two banks changed in total 200€ into

, which I would call a job well done. Unfortunately elsewhere in France I received only few notes from gas stations and stores.
Back to Berlin I brought the following pile of fivers: 480 notes, if I'm not mistaken. Let's see if anyone manages to find any of those later on...
