It is very common and polite for Japanese to address a complete stranger as 'old lady' or 'grandfather' or 'elder sister' or 'elder brother' or 'Mr. Policeman' or 'miss' or 'boy'. - Obasan - Ojisan - Oneesan - Oniisan - Omawarisan

In general, -san is the most common suffix. It is moderately polite and is translated as Mr. and Ms. etc.

You should put -san after the name:)