"I have an old book, how much is it worth"
"Do you have it with you sir ?"
"No - do you think I should have brought it along ?"
"Thats depends what you want to do with it. Who was the author?"
"I don't know, I can't remember the title either. But its very old. How much are old books worth?"
"Well how old is old ?"
"Oh very old, at least 5 years old. Its even in hardback."