Guy comes in - also the worst for drink (Must be a day for it), and asks if I buy books.
"Sometimes", say I "What sort of books are they"
"Oh I don't know, all sorts" He replied "How much will you pay me for them"
"I would have to see them, it varys from a pound or so, up to a few thousand, usually the former"
"But you must be able to give me some idea - can't you guess?"