My ranger will be taking a wolf companion at level 4, then the feat boon companion at level 5.
I plan on using the Bodyguard archetype from the Animal Archive.
Any advice on what feats to take?
I assume I want combat reflexes, bodyguard and in harms way, eventually. But I assume I want armor proficiency as well.
I have never made a companion before so I really could use advice.
Your PC and your AC should consider the Lookout Teamwork feat. Combined with the 3rd level ability of the AC you'll be allowed to always act in the surprise round.
So do you just want a meat shield or do you want an animal companion that's good at doing other stuff, too?
I think his first thing will be a meat shield for my archer ranger, but he will need to stealth and scout with him as well
Those feats seem like they'd be good for what you're looking for. Armor Proficiency is definitely a must-have for any combat-oriented companion, but given that it's not the primary role (and barding would increase the armor check penalty, reducing its effectiveness in stealth), I'd hold off until your next feat.
so maybe
Combat Reflexes, Bodyguard, skill focus stealth to start?
Then pick up armor and in harms way next?