Your Amazon shopping cart could soon include a late-model used car from Hertz. The rental-car company has started selling its used vehicles directly to consumers through the online giant.Hertz shares soared as much as 17% on Wednesday after the company said it would sell its used cars on Amazon’s automotive marketplace.

The news could affect shares of car dealers or online platforms such as Cars.com. Amazon Auto represents competition for listings and used-car inventory. Carvana stock dropped 6.3% in early trading at $322.52. CarGurus stock slipped 1.6% at $31.92. Cars.com stock was off 0.1% at $12.05.

Hertz announced it has joined Amazon Autos to start selling pre-owned vehicles to boost the company's profits.