eour hobby is collecting coins, ...?

... isn't it?

(такая задумка?) Например:

- Your hobby is collecting coins, Mr.Hodorkovsky, isn't it? 

- Yes, I have lots of coins, also bank notes, banks, ships, factories, oil fields and perhaps something else I even don't know.

- Well, now you are arrested. You have nothing since now.

ответ ( если это должен быть "хвостик")isnt it