Not sure how that would work. If you had two triggers within each other, one turning the wall or usable off and the other turning it on they would conflict. If you had the off trigger be surrounding the on trigger so that as soon as the activating player left that area that wouldn't work either as multiple players would cause that not to work. The only real workaround is either the target_print method or having one trigger target a func_wall with the message that only displays it for a certain amount of time with the wait time on the trigger_multiple equalling that time. So if the player is in the area for more than the timer it would keep displaying, but if they walked away then it would turn off.