In this video guide I will show you how to defeat each type of bounty hunter. Now you will more than likely get this without even trying. The first time you come across them is right after you get your force pull ability. You will fight one and then be captured. Once you make your way out of jail, then you will fight the shield bounty hunter again. Once you go back to planets after beating the shield bounty hunter, they will be in the maps randomly. They will take the place of normal enemies. The other two types you will need are a robot and a bounty hunter like Bobba Fett, with a jet back. I will list some areas where you can find them. Once you kill each type the achievement will pop.
Robot and jet pack bounty hunters: Zeffo, Windswept Ruins - 00:42 - 02:15
Robot and shield bounty hunters: Zeffo, Derelict Hanger - 02:18 - 03:14
Robot bounty hunter: Bogano, Hermit's Abode - 03:18 - 03:40