There is a parking lot directly behind the studio, run by Millennium Parking,
a separate company.  Enter at 157 W. Chicago.
Hours are: Monday to Friday 7am-6pm, Saturday 9am to 6pm, Sunday 9am to 5pm

Parking rates for Millennium Parking are:
Weekdays: 12 hours for $14 // 24 hours for $30
Weekends:  12 hours for $10

It is often less expensive to do street parking which is available nearby on
Superior Street, Chicago Ave. and LaSalle Blvd.

Spothero is a useful app for finding parking nearby.