Keep it simple
Make it as easy as possible for your prospect to buy your product or service.
Don't waste their time with lengthy phone calls, emails or letters - short, sharp communication using bullet points will keep their attention.
Their time is also money - if you bombard your prospect with calls and information you will lose them.
By offering just the right amount of information and not wasting their time you are more likely to make the sale, if the prospect wants more in-depth information, they will ask you for it.