Interlaken is small and boring kurort with lots of watch shops and jelwery butiqes but very good busking.
Very ralible place is small old hut where grass is keep for cows over lake Burgseewli. Comfy and private! Take bus 103 from west trainstation and get of next to petrol station. location: 46°41'49.3"N 7°53'00.5"E Also there, in front of pink hotel is dumpster where you can find clothes
You can leave your stuff safe in locker for dogs in front of Migros supermarket. 2 Fr deposit.
Migros restaurant in west interlaken.
Very good on central grass field, also next to a fountain and migros. No problems with Police over 1 month of 2015.