The Common Laywer by Gimenez

Second Hand 

Andy Prescott is the most laid-back young lawyer in Austin, Texas. Specialising in traffic law, he operates from a small room above a ramshackle tattoo parlour. He rides a trail bike and spends way too much time drinking beer in the sunshine. Ambition has never been Andy's strong point - he prefers to take it easy.

That is, until one of Texas's wealthiest men walks into his office. On the spot, billionaire Russell Reeves retains Andy as his lawyer and, in exchange for some easy legal work, pays him more money than he has ever earned before. Andy's life is transformed.

But nothing comes for free. Russell is a desperate man whose sole aim is to save his eight-year-old son, Zach, who is dying from leukemia. He is prepared to do anything - even if it means putting Andy's life in danger...