["My neighbor is out again having a party...I find it strange because he yelled at me on a night before when he was working...but it's okay when he wants too?"]
No, not if he is being loud and rude, that is never okay
My neighbor is out again having a party...I find it strange because he yelled at me on a night before- but he has decided when HE isn't working- it's fine to be loud later at night