One had to be very careful about biographies of Hitler in general. For obvious reasons, many people wrote "biographies" of his where the relationship to reality is between tenuous and nonexistent.
For example, there is Speer's popular "Inside the Third Reich", which always reminds me of "verbal" in The Usual Suspects -- he puts TONS of tiny little details in every chapter EXCEPT the ones that actually matter, e.g., his knowledge of the atrocities or his control of slave labor, which are given -- in the entire book -- at most a few paragraphs, much less than is given to, say, Hitler's table manners or Goering's love of luxury.
Another famous but worthless work is "The Life and Death of Adolf Hitler" by Payne, which has Hitler doing numerous things which he never did: faking art, being dirty with lice, engaging in sadomasochistic sex, going by the name of "Schikelgruber", visiting his half-brother in England, believing in astrology, sending a delegation to have a secret meeting behind the lines with the Soviets in 1943, etc.
An excellent review of such spurious biographies can be found in Waite's The Psychopathic God, in the chapter "A Note on Spurious Sources". For example, he notes that the stories of Hitler being a down-and-out bum in Vienna has some basis in fact, but in reality he was not nearly as "down and out" as he was often portrayed. This description of him, notes Waite, comes mainly from two lifelong bums and petty criminals who tried, during the 1930s, to cash in on the fact that they were living in Vienna boarding-houses at roughly the same time when Hitler was. Naturally, they invented numerous "spicy" details to sell their books -- fables that were later repeated in history books.
Some historians fell for these liars' descriptions of Hitler in Vienna since each of these "biographers" vouches for the accuracy of the other -- which, Waite notes, is "not unlike accepting mutual character testimonies from Uriah Heep and Seth Pecksniff".
