The CTA visitor passes are $5 for one day, $12 for three day, etc, and are good on Pace, the suburban system. As well, on weekends, Metra is only $5 for unlimited rides for both Saturday and Sunday, and many routes run on weekends. Midway aiport hotel cluster is worth investigating, frequent bus service and free hotel shuttles - if you have a hotel that is near O'Hare or Midway and has this, you're set - so check out the rates for airport hotels, cheaper than downtown, but more than more far-flung suburban hotels.