These transactions accounted for 14% of all completed workouts in 2010, up from 4% in 2000. Shelley Poland, a vice president at Freddie, and Robert Hagberg, the associate director of fraud investigations, said in a blog post Monday the mortgage giant sees short sale fraud on the rise as well — especially when real estate agents fail to disclose other parties involved in the transaction, who will rig sales at a low price and hide better offers from Freddie and the distressed homeowner. "Then, after the house is sold, the fraudster can flip it a few hours later for the better price and walk away with the profitable difference," the Freddie executives said. "By concealing the higher offer, short sale fraud worsens losses to home sellers, Freddie Mac, and taxpayers. It also throws another wrench into the housing recovery by undermining the trust and transparency at the core of any real estate transaction." Short sales fraud is now the top priority for Hagberg's investigation unit.