What's risk?
It is the potential cost to the individual customer if he/she makes a mistake. It's not just the money, although that is part of it. It is also the social, psychological and emotional cost that your customer will pay if your choice isn't the best one. The lower the risk of the decision, the more likely your customer will say "yes" to you - regardless of the price. Become comfortable with this concept of risk first, and then use it in your sales efforts. In order to really understand risk, you must first see this issue from your customers' perspective. Try to put yourself in their shoes, and calculate the amount of risk that you expect your customers to take when you offer them an opportunity to say "yes" to you. Make sure they know and understand that all your work is 12 months - 12,000 miles (or whatever your warranty is)!