Salesman: Andy...let me put it this way if you were me, how would you convince you to buy this system from us now?
Andy: Well, <Salesman's name>. I always go for win-win when I can. You give me one for free and, in return, I'd write you a glowing testimonial and act as a local demonstrator one day a month.
Let's see how far THAT gets you.
He's using a technique well-known in coaching circles in which the client solves their own problem.
E.G "If I were to tell you one thing that would make you stop smoking immediately, what would it be."
Or, "If I could give you one idea that would help you double your monthly income without doing any extra work or spending any extra money, what would it be?"
It's a great technique for coaching, but a really bad one for salesman to use. If anyone gets the same call, tell them that the technique they're using is unethical.
Tell them, "You're using a coaching technique designed to help me solve my own problems to help you meet your sales targets - and that is evil."