What to do about a "deposit" that won't be returned?

My friend gave a man $250 for a duplex she was interested in. She changed her mind and he won't return her $$. She said <> told her the $250 <> take it off the market but he would still show it to her and do a credit check. He won't return it bcz he stated that he take it off the market and she isn't due the $$ bcz she changed her mind.. I read the papers she signed when she gave him the $250 and they clearly stated that <$500> would take it off the market. If she changed her mind (and other things) after paying the $500 then she isn't due a refund. Basically, he's stating she isn't due the $250 bcz he took it off the market. She asked for her deposit on 3/18 and he stated it's off the market (bcz of her $250) and no refund is due. We went on the website the same day and it's still posted! She printed it and the printout has the date on it. He says he's just the property mgr, but won't give her the property owner's name or #. What can she do to get her $?