Here is a small outdoor parking space for the nearby shopping mall. It is also less than five minutes from the train, tram and bus stop. Here are some classic parking-space-hides available and Zurich is now also sorted whit this kind of drive in caches
Depending on the time of the day you have to take care of many passers - they should not notice any thing so the jar will not get lost. For example you could fake to tight your shoes. You do not need to step in to the railway area or the bussy main road. Please close the jar well and hide it in the same spot.
And now I wish a nice drive & grab.