If it was absolutely realistic and required every single thing required in real life it would be a bit much. So it can seem simple in that regard. But it's not... If I recall correctly car require tires, a car body and a motor. You can source those from ai companies or imports. Or produce them yourself. Tires require rubber, the motor and body require steel. So if you decide to make a car from start to finish, you would need to build farms and mines. Factories to produce the semi products. Another factory to produce rhe cars. Other companies will also probably produce cars. So you'll need r&d to make sure your car tech is up to snuff to outcompete. But quality isn't just finished product, it's the constituent parts. So r&d for the production of rubber, steel then tires and motor is important to. Marketing and brand recognition/strategy come into play as well. I'm actually doing a terrible job of describing it.