Kilpatrick, on trial on corruption charges, has a public defender because he says he cannot afford to pay one.
Kilpatrick's finances are being reviewed by parole officials and Wayne County prosecutors, who said they have found he flies for free on the weekends between Texas and Detroit, and until recently stayed for free at a luxury downtown hotel, The Detroit News reported Monday.
He moved out of the hotel and into his mother's house in early October after the News raised questions about where he was living.
Kilpatrick is on parole for probation violations on felony charges relating a text message scandal. In the interim, Michigan officials have taken over supervision of his parole from Texas.
In the current corruption trial, he is accused of taking money from a city fund for his personal use and using campaign donations to pay for trips and personal expenses.
Prosecutors have not yet found any proceeds from Kilpatrick's autobiography.