Response from Mara:
Thanks for the comment about the tram ticket. It is right that the tram ticket called "Kurzstrecke" (a tram ticket for up to 5 stops, so from Bahnhofquai till Schaffhauserplatz) is cheaper than the "Einzelticket". The Schaffhauserplatz is really not far from my place, only 7 minutes by foot. I will add this information on my description.