When you leave the company it’s expected that you will leave your mac completely formatted, so the mac can be passed on to another colleague.
Besides that, make sure that you hand in all Lifely property on your last day at work
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Erase all content and settings on Mac
It’s possible that you had to work on a client computer, this makes things more complicated, because it could be possible that the laptop is coupled to a specific person and because of that the laptop can only be handed in by that person. We sure want to stay in contact with you but not for the reason that you come back to hand in all hardware to the client ;)
Make sure to have all client related hardware matters resolved before you leave