A quick Google search of the "brizzzyredhead" moniker turns up a comment made by the author in late May 2008 on the former roommate's now defunct blog. http://i.imgur.com/dK1Sx.jpg
Mark Horvath, founder of the well-respected homeless outreach program Invisible People, took back his support of her book after discovering inconsistencies about himself & his interaction with the author in the book.
Someone named "Sage," who claims to have been acquainted with the author for the past two years, also takes issue with Karp's version of events. http://www.goodreads.com/review/show/1544
This book may be an entertaining read, as "Preston" suggests. Even so, it would seem that it belongs in the fiction section, rather than the non-- and that it should be taken with more than a few grains of salt.