CHICAGO — A man who expected to be paid a finder’s fee for handing over a 16-year-old Chicago girl to a pimp has pleaded guilty to federal sex trafficking charges.

Charles McFee says he was never paid the $250 promised by the alleged pimp, Joseph Hazley, for Desiree Robinson. According to McFee, Hazley claimed the girl was costing him too much in makeup, clothes and gasoline needed to drive her to meetings with customers.

Under the plea deal, prosecutors recommended the 26-year-old McFee receive a 7 1/2-year prison sentence in exchange for testifying against Hazley.

McFee said he met Robinson on Facebook and a sexual relationship developed. He took her to Hazley and watched him set up an online sex ad featuring Robinson.

Hazley allegedly took Robinson to a suburban Chicago home to have sex with her alleged killer, Antonio Rosales, who is awaiting trial.