Why are cars so expensive?

Answer

because they have so many things that you can do in them that it makes it hard for people to give away a car for $800 or so on

You didn't put the brand of car in the question, so it is impossible to give you the specific reason.

Most expensive cars are expensive do to the materials they use( leathers, aluminum, magnesium, carbon fiber, rare wood trims). Hand assembled cars (E.I. Aston Martin, koenigsegg) have a lot of man hours/labor time in building it that makes production expensive.

They provide cutting edge technologies that aren't available in cheaper cars for a couple years.

Some cars are expensive just because of the brand name / mystique / horsepower it has/ status it insinuates , or it's limited production.