Residents are allowed to have two garage sales per year lasting not more than four consecutive days. City of Topeka
Code Section 114-37.
Signs
You may place temporary signs on your property (and private property other than your own with the permission of the property owner) but ONLY between 5PM Thursday to 5PM Sunday, and NOT in the public right of way, which is generally the area between the sidewalk or water meter and the street.
Violators may be fined $50 and assessed a $30 removal fee, per City of Topeka
Code Section 118.