Options include placing an ad online or taping a For Sale sign to the windshield and waiting for someone to give you call. If you don't want to deal with calls, you could also sell it to a car store such as CarMax. The point is, there aren't – yet – any laws prohibiting you from selling your car any way you like. Including, specifically, directly – to the person who wants to buy it.

Nor are there laws – yet – prohibiting people from buying cars any way they like. Including, specifically, directly – from you.

Well, as far as used cars.

With new cars, on the other hand, there are all kinds of laws dictating how – and where – a sale may be transacted.

As at a dealership.

For the most part, you are not allowed to deal directly with the manufacturer, the company that built the car. Which you might wish to do, in order to cut out the middleman – and save yourself some money.