Catch them in a calm moment and ask in person, not through the window or when you are frustrated. Keep it short and specific, like "Hey, I know parking is tight, but when you park across the apron I can't get in and out of my driveway. Could you leave that part clear?" Use I statements and give concrete times you need the space, so it sounds like a practical request rather than a complaint. Some people genuinely do not realize that the apron and sidewalk area are part of the driveway, so explaining that briefly can help. If you miss them, a friendly note under the wiper with your name and unit and the same wording works too. You can add a gentle nudge like "blocking a driveway is ticketable here and I would rather not call it in" which makes the stakes clear without being hostile. If it keeps happening, take photos for a couple of days and use non emergency parking enforcement or your HOA to handle it so you are not arguing neighbor to neighbor.
You can also put a small "do not block driveway" sign on your fence or garage or ask the city about painting the curb edge if that is allowed. Avoid cones or saving the space on the street unless your city permits it, since the street is public. Through all of this, stay friendly and thank them when they do leave it clear, because positive reinforcement goes a long way.
