How to present two business models within single app navigation?

i need your help here. we have two business models in single app, the first model is car classifieds and the second one is buying car online, and most of our users cannot tell the difference between them and don't have the curiosity to check the second business model. What best practices in navigation to assure business models are accessible for the user and can tell the difference between them, because they have different user experience.

i appreciate your help, thank you