A Welcome Grave by Michael Koryta

A former cop turned private investigator becomes the prime suspect when a wealthy rival with whom he shares a violent history is murdered. Hired by the dead man’s widow to locate an estranged son and settle the estate, he follows a trail of missing money, old grudges, and buried secrets that draws him into a web of legal intrigue and lethal deception. With police pressure mounting and evidence being planted, he must untangle a conspiracy and expose the real killers to clear his name.

Purchase from Bookshop.org