Bidding log:
Tried for several days to book 10/8 to 10/11 but eventually realized that the 10/8 day (a Saturday and the day of the Chicago Marathon with 140,000 non-residents expected) was really skewing my bidding ability so I tried 10/9 to 10/11 instead and finally scored a great deal.
First attempt: $90 4.5* Magnificent Mile Gold Coast
Second Attempt: $95 4.5* Magnificent Mile Gold Coast + Chicago Loop Grant Park
Third Attempt: $100 4.5* Magnificent Mile Gold Coast + Chicago Loop Grant Park + Downtown River North
Won the Westin for $100/night in Downtown River North on the third try. Very happy.