It took the parents less than 24 hours to find new places to live?
I caught this earlier today when I was watching the movie:
Robert comes home late on Christmas Eve after going to the cheesecake factory and him and Nancy decides to divorce (obviously after Brennan and Dale throw him down the stairs), the next night (Christmas Day) they are sitting at the dinner table and he tells them that he's moving in with his friend and Nancy found a townhouse in the city. So that basically would have meant that they really must have really done some house hunting Christmas Day after deciding to divorce the night before and finding new places to live less than 24 hours later.