Not bad, considering that he was in his thirties when he wrote those movies and had to channel the mindset of younger people. At this point he was ready to become more than just a screenwriter/director—he was ready to become a production empire, Hughes Entertainment.
Using this production company, he had rapid success with movies like Planes, Trains, and Automobiles (1987) and National Lampoon's Christmas Vacation (1989)—both of them holiday classics. By the time the swingin' 90s rolled around, John Hughes was in position to produce the holiday classic to outsell all holiday classics: he produced Home Alone—in addition to writing it—while letting Chris Columbus (writer of Gremlins, which also involved holiday mayhem) take the director's seat.
In addition to the unstoppable John Hughes mecha-zoid producer force, Twentieth Century Fox got on board and helped amp up the budget. Originally, Warner Bros. was supposed to be the distributor, but when Fox took over, they let the budget jump from $14 million to $17 million.
This was actually a decent amount of money for a movie that takes place mainly in the environs of a house in Chicago, plus some airports. But the amount they made in box office revenue after the movie was released was staggering: $476.7 million.
That made Home Alone the most successful holiday movie of all time (at the time). Not too bad for a Chicago boy who made his name channeling the mindsets of people twenty years younger than himself. (Source)