To do business I absolutely agree with records and for email when talking business. I usually ask that a person emails me for the actual business talk when I sell/buy snakes, so I agree with how valuable writing and email is... But to get the initial attention of someone to start things off is where a call is best.
Should business talk occur on that initial call, just ask the person to send a quote or confirmation of what you talked about before proceeding. Check over the quote and don't proceed until you have in writing a proper representation of what is going on.