D Is For Deadbeat by Sue Grafton

In this mystery novel, private investigator Kinsey Millhone is hired by a man named Alvin Limardo to deliver a $25,000 check to a teenager named Tony Gahan. However, Kinsey soon discovers that Limardo is actually a con artist named John Daggett, and the check bounces. As she delves deeper into Daggett's past, Kinsey uncovers a web of deceit, betrayal, and murder. Her investigation leads her through a series of twists and turns, ultimately revealing the dark secrets and hidden motives of those involved, while Kinsey navigates the dangerous waters of deception and justice.