To save $ you might consider renting a car when you get to Chicago and staying at a Hotel 15-20 minutes away. If you are driving to chicago thismakes things a lot simpler. The cost of car rental and parking should be a lot less than pying $300 for a hotel. Plus it gives you mr mobility for seeing stuff further away from the show location.
If you have never been to a show I think you may find the educational sessions worthwhile.
There are also Public transportation options from closer Hotels like the Travel Lodge which is about $175.00 / night.
If you want to be a half hour away, Heart of Chicago motel is $60.00 / night and it is not in a bad area.