If you pretend to use public lockers to keep your luggage safe while you wait for a bus, make sure you don't give your key to anyone that offers you to help you to put your things inside the lockers. This person can swap the keys and then you are called to board in a bus or train and you try the keys and that keys just don't work. Some people will panic and let the luggage behind especially if you want to catch an airplane. If this happens and you cannot lose the bus or train just call tourist police and explain the situation but there chance that you gonna lose your stuff. So to prevent this always keep your stuff with you or at least keep your key with you.