If you haven't yet visited CCOM do not be surprised that it is not at all located in the city of Chicago.... it's in Downers Grove, a suburb 30-40minutes out of the city. I'm not sure which hotel to stay at but if you call the school I'm sure they can give you some suggestions.
As for the interview - the day moved pretty quickly for me, I think there were 9 other interviewees. Everyone was really nice and the atmosphere was super relaxed. The questions were typical, not too hard. There are 3 interviewers per applicant so it moves pretty fast bc they all ask questions; I felt a little overwhelmed. You only get 30 minutes so try to say as much as you can so they can get a complete feel on who you are. Some questions that I thought were a little difficult to answer were the following:
1) You're working at a private hospital located just down the street of a city/public hospital, but a homeless man w/o insurance walks into your ER. What do you do? What do you tell him?
2) Is there anything in your academic profile that you are not proud of? What could you have done better?
It's important to remember when answering these questions that they're not looking for a specific answer but rather how you think. They're looking for a reason to accept you not reject you! Hope this helps a little, good luck!
Tough/common interview questions? Thanks for any input! I have an interview at CCOM on Tuesday. I already took a look at the interview site on student doctor, but was wondering if anyone who already had an interview at CCOM has any advice? What hotels did you stay at? Positive experiences? Tough/common interview questions? Thanks for any input! 
