Truth in advertising

My young nephew is selling his car. Well he wants to and has a notice in its window to attract interest. Unfortunately he seems to have done too good a job. Each time he looks at the notice he thinks "I wouldn't mind owning that". One of the key features is the six-speaker sound system - which may or may not be a four-speaker system with another two wired in and knocking around in the back of the station wagon. Still he has had a bit of success with previous sales - and on complaints. I wonder if this could be the key to a career?