There are four stores that I recommend for students to use for renting violins.
The stores are:
Kenneth Stein Violins located in Elmhurst, IL
Midwest String Rental located in Downtown Chicago, IL (Loop)
Austin Music Center located in Oak Park, IL
A440 Violin Shop located in Downtown Chicago, IL (Roscoe Village)
I have had great success sending students to the A440 violin shop and have just recently discovered the Austin Music Center. I provided the Austin Music Center as it is in a convenient location in Oak Park.
Another Resource for violin accessories (such as rosin, shoulder rests and music) is SharMusic.