say he puts in temp drainage provisions to remove water from the roof, and it ponds from your neighbours property, what happens then? im sure the builder will not be responsible from water offsite coming onto his site. He may then push back onto you, since you have made it an issue now.
Its construction site, the ground will get wet when it rains. Water will pond on your site until it is finished. That's not a lot of water anyway.
Most engineering drawings will show drainage toe at bottom of excavation batter and even if they don't builer is required to manage site drainage. And yes I have seen slab heave before house was finished.