We have 36 Level 2 chargers where I work. They is a large light on the top of each charger which indicates if the car is currently charging, plugged in but not currently charging or is finished charging. We can also "check-in" to the charger and indicate how much charge we need and when we plan on leaving the charger. I also place a sign on my dash which has my work extension as well as my expected departure time.
I wish we could convince our building to install more chargers. I work in a 41 story building that is only 10 years old with at least 50 EVs that park there daily and they've only got 3 Level 2 chargers, 2 of which are out of order because some dumb ass drove off with the cord wrapped around their tire and ripped it out of the base, disabling both ports on that unit. That happened 4 or 5 months ago and not fixed yet.