Hopefully this post is in the right place...

I'm planning to make a trip later this fall to Chicago. I'm 19 and will be traveling alone. I am wondering how strict hotels are about a minimum check-in age. I am planning on staying at the Four Seasons and will be using a major credit card in my name, but I've heard the minimum check-in age for the hotel is 21. Does anyone have any advice for checking in?

One more thing ... I currently have the room reserved for two. Would it be better to only have it listed for one?

Thanks!!