How long should I wait before interview?

At the age of thirteen he began writing as a "mountain reporter" for small-town newspapers. He used his earnings as a reporter to enter law school, but soon had to withdraw for financial reasons. The turning point in his career is considered to have been in 1908 with his assignment, as part of a series of articles about famous men, to interview industrialist Andrew Carnegie, who at the time was one of the richest men in the world. Hill discovered that Carnegie believed that the process of success could be elaborated in a simple formula that could be duplicated by the average person. Impressed with Hill, Carnegie commissioned him (without pay and only offering to provide him with letters of reference) to interview over 500 successful men and women, many of them millionaires, in order to discover and publish this formula for success.