my brother is a Honda salesman...

For a stock deal on a Civic, he'll make between $100-200.
If you finance it at the dealer he gets a good cut
If you add extras like special radios and other dealer installed stuff, he gets a % of that too.
Even better is buying a longer warranty, that's a big up sell item..

They make much more $ on used cars..

and FYI, if you're trading in a full size truck or SUV, be prepared to take a huge hit , like 20% off wholesale value.