Trophy Hunter.
I'd even say a good ol' slumber Hexcrafter.
If you really want to get fancy, perhaps a vanilla brawler with Equipment Trick, focusing on rope and net tricks.
Cleric/Ranger 10
Max Wis.
This guy would be one of the best when dealing with a single target. Force multiple high will saves per turn and the target will be terminated on one failed save.
Take the Corpse Dodger Archetype to only have Undead as your Favored Enemy.
Use the Ranger Spell Instant Enemy to let him treat his target as an Undead, and use Command Undead/Disrupting Weapon to wreak havoc upon his bounty.
Command Undead works on enemies with a hit dice up to his cleric level, while Disrupting Undead is a one-save kill which would work on enemies up to his caster level. Take Additional Traits to boost the Caster Level for Disrupting Weapon by 2.
Pros:
*Neither spells are affected by Spell Resistance
*Can use Hide from Undead preemptively.
Cons:
*Not great against several targets.
*You'll need to get close to the target.
*Rangers spells are extremely limited, so you'll at best have two lv 3 spells at character level 10. Could be circumvented by scrolls/Pearl of Power.
*Won't work against enemies with higher Hit Dice.
*Extremely cheesy
A good bounty hunter needs
1. To be able to find their target. Divination magic would be really helpful but likely not enough on its own. A high skill check for gathering info (Diplomacy, unless you've changed it; some do) and tracking (Survival) for the mundane way.
2. To be able to get to their target. If they're living underwater or surrounded by their gang or hanging out somewhere trapped to the heavens and back he needs to be able to deal with that. So yeah, the full stealth/trapfinding package, and some stuff (ideally spells, 2nd best items) for dealing with whatever nasty environments he might encounter.
3. To take out targets without killing. A full spellcaster would be easiest; unless you go full tetori monk grappling is iffy against someone who happens to have planned to deal with it. Nonlethal damage is possible though.
Just thinking aloud so I can see what might work.
Urban Infiltrator Inquisitor (redemption inquisition) // Sniper Slayer could work. Between the classes they have the skills and stealth very well covered, the inquisitor spell list is pretty good for finding and chasing people down and pincushioning the enemy with arrows (or a single Named Bullet spell on an arrow if he's 10th level) is a viable tactic which he can choose to do nonlethally.
Shadow Seeker Sorcerer // Stalker Vigilante is about as good at stealth as is possible, though less amazing at the other skills. A careful choice of spells will make him better at most of the required magic. Full caster, after all. Merciful spell can turn blasts nonlethal and/or he might pick up save-or-lose spells.
Slayer // Vigilante ... you'll need a bit of magic. Maybe core Slayer // Warlock Vigilante. Not quite as good as either of the two above, but it has its own tricks like the warlock talents social simulacrum and tattoo chamber.
He'll be a gestalt npc who works alone. I was originally thinking slayer/vigilante or inquisitor. He'll be lvl 9 or 10. Suggestions?
That depends mightily on whether you're the "bring em back alive" or do you just bring the heads type.
