Minor collisions or fender-benders can result in expensive repair costs for a number of the newly-introduced mini-cars, according to the Insurance Institute for Highway Safety. Larger vehicles have more substantial material surrounding the engine compartment and suspension. With the design of ultra-compact cars emphasizing passenger protection, damage to the crumple zones on many of these vehicles impacts vital engine and steering components. With these types of vehicles costing more to repair, owners can expect to pay higher insurance rates for mini-cars.

In low-speed crash tests on front and rear bumpers at speeds between 3 and 6 miles per hour, the IIHS calculated repair expenses from $474 to $3,701. IIHS senior vice president Joe Nolan remarked to MSNBC that bumpers should be constructed so that in these scenarios, damage should not exceed the standard car insurance deductible of $500. With damage in the range of $1000 or above, current bumper design on these types of vehicles does not protect any of the more vulnerable features, such as headlights and grilles.

In the four tests performed to the front and rear bumpers, the Kia Rio would have needed an average of $2705 in repairs, with a high of $3701. The Smart Fourtwo scored the lowest in repair costs with an average of $899. To score the industry's top rating, manufacturers have to hold average repair costs in these tests to less than $500, which none of the seven vehicles tested achieved. This is the first year the IIHS has designated a "good" to "poor" rating for bumper crash tests, with the intention of allowing consumers to specifically choose vehicles with bumpers which perform well. Vehicles which perform poorly in bumper crash tests are usually assigned a higher car insurance premium.