Roach
Term used in car sales to describe a customer who never buys, and who wanders around the showroom like a cockroach.

Usually a "roach" has lousy credit and can't afford to buy, or he comes in regularly and talks shit how he will buy, but never actually buys a car because of variuous resons, like credit, money, or his indecisivness.
Don't talk to that guy standing by the canovertible.  He's a raoch and will waste your time.

This roach has been in here every other day, and he still makes up excuses not to buy.  Stay away from him.