Custom Elevators
Currently, I've been working on a new, unique aesthetic theme. I wanted to make a custom elevator for it, but I could never get the elevator to work. I've tried looking it up, but I get no results.
Does anyone know a good tutorial on how to make custom elevators?
Emm, no because that's not what conventional Portal 2 mappers do. You can try parenting a lift model to a brush entity. Just look at how a4_arrival_elevator_logic is made.
I didn't mean the actual elevator, but it's surroundings. Like what josepezdj or Fourth Reaper does. I really like it, but when I try to make my own, hammer crashes or it doesn't work.
I think I know what you want now...
So you are trying to add like pipe's, vines, debris, etc. in the elevator room? To do this simply choose an elevator instance, and edit it to your specifications. Just remember to save it under a new name so you don't mess up the original elevator you were working with!
To edit the instance place the elevator in the map and choose "edit instance" after clicking on it.
Hope this helps out! Goodluck 
Thanks, that helped.
(By the way, it was more so changing textures than adding entities.)