Sean Kingston might want to check the Los Angeles subway schedule -- since he lost two sets of wheels to the repo man in less than a week.

TMZ reports that Kingston had his Mercedes wagon towed while he was shopping at a mall in the L.A. suburbs last week, because he was three months behind on payments. He went to his backup ride to hit a party on the Sunset Strip this past Wednesday, only to find the repo man waiting with another truck -- which he used to tow away Sean's Bentley.

The Mercedes is headed for the auction block momentarily. No word on what will become of the Bentley.