Thanks for the post!
Can you please tell me if this is the type of game where getting the 100% achievement/trophy will be near impossible if I don't use a checklist from beginning to end? Or will I be good just playing normally and then mopping up for 100% after I beat the game?
This.
After you beat the game you unlock free roam so you can mop up achievements then.. I would try and complete small achievements and work towards the goals for earning the PERFECTIONIST achievement while playing normally (like rising the bike and skateboard, egging cars, etc.), but you could just go through the story and worry about it after.