@Jordan Deeney
Depends on the install but here's some rules of thumb/observations that are specific to my area:
Basically, the AHJ wants you to permit just about everything. That said, if the existing system works they typically let you use it. One example in particular is pretty telling for a heuristic to know when you HAVE to do something - which is, electrically, when you open up a wall, and existing wires are exposed, generally speaking if it's old 2 wire insulated wire, the inspector will want to see that changed out. However, if your remodel does not require you to open up that wall, typically they will let you leave it in place, and just use a 2 wire receptacle.
You may know something I don't know, but I'm not aware of getting AFCI outlets. They typically are breakers that need to be installed at $40-50 a piece in the panel.
I think you're asking the right question, but I'd suggest you look to ask this question specifically to another seasoned investor on an application specific basis.
We have paid a local guy here $100 to be our 'go/no go' inspector before we buy a house. He likes us and likes passing along his knowledge but especially because he does rentals, his experiences are very very valuable. If you can do that as you're looking to scope/cost out a remodel, you'll be way ahead.
Hope this helps and good luck!