Dirty Thirty by Janet Evanovich

Stephanie Plum is searching for diamonds and jewelry.  She knows who took it and wants to capture them, too.  She is a bounty hunter and needs the money.

She finds out that the jewels are fake.  The man  selling them is a fraud.  He shot a homeless man.

As she looks for the jewelry, she also looks for the homeless man.  She sees several buried men but not the one she wants.

Then the man who has her is going to kill her.

You need to read it to see how it turns out...