I used to own the out-of-print paperback edition of this book. I foolishly gave it away.
Sanchez begins with his life as a young, aspiring, underworld figure, emulating an older, already established relative. He worked in a casino, and also began to take up photography. (By his own account, Sanchez was commissioned to photograph the cover of the first Moody Blues album.) An acquaintance, London art dealer Robert Fraser, was deeply in debt to another casino run by an underworld boss, and dramatically confided his problem to Sanchez. Sanchez nervily approached the casino boss, to keep Fraser out of harm's way. Then -- aware that his own casino subtly rigged gaming against its customers -- Sanchez arranged for Fraser to win money from Sanchez's gaming table needed to pay off the debt. Fraser was profoundly grateful and so introduced "Spanish Tony" to his new, up-and-coming, hip young friends, the Rolling Stones.
Spanish Tony's common bond with the Stones was his access to, and penchant for, hard drugs. Ultimately, he would become a heroin addict.
This book mostly concentrates on Sanchez' close access to Jagger, Richards, and Jones, as well as Stones' ex'es Anita Pallenberg, Marianne Faithfull, and Bianca, between the years 1966-73, which was the peak of the Stones' artistic success. Watts, Wyman, and Mick Taylor are hardly discussed, and receive less than 2 pages each.
Sanchez acknowledges the shallowness of his friendship with and access to the Stones as being based on his connections and ability to discreetly obtain large quantities of drugs in both England and the south of France. He simultaneously served as Keith Richards' (who spent the most on drugs) connection to and insulation from the underworld. Ultimately, Sanchez severed his relationship with the Stones and went into rehab. There can be no question of Sanchez' close relationship with three of the Stones, if the exclusive candid photos in his book are any indication.
Anyone who wasn't present for the events which shaped the book can't know for sure, but, as a aficionado of insider celebrity bios, this book is presented with sufficient insight and clarity to convince that it is principally a true story.