Fair exchange, what!!
A butcher saw a Lawyer passing by his shop one day, and asked him: Mr.
Attorney, what would you do if a dog came in and stole your meat?
Lawyer replied: why? of course, I'll make the owner pay for it! The
butcher said: That being the case, you now owe me $15 because it is
your dog. The Lawyer replied: very well, just deduct the $15 from the
$25 you owe me for the advice I've just given, I'll collect the
remaining $10 the next time I pass by here.