If you need to use their driveway for some reason, YOU ASK POLITELY. My neighbor has authorized me to park in his driveway when I need to.
But don't occupy the space without warning. They might need it for their own cars when they drop by, or the workers might need that end of driveway to park or unpack stuff.
If your neighbors are having an addition put on their house and they have a pod/storage unit in their driveway for the duration of the project, do you think you are allowed to block their driveway by parking at the end of it?