My husband has those sleazy guys steppin and fetchin by time he is done. ..lol
Do some research on the internet, they hate that. Come prepared on what you want and want "toys" you want in the car. Know the blue book value of the type of car you want. That way you know a bargain when you see it. Also makes a nice bargaining chip.
Most important, don't except anything less then what you want. If they can't offer it, walk away. If they want a sale bad enough they will seek you out to come back. This worked for us on my new truck when we bought it. We wanted nerf bars and a lower price (less than 20k, sticker price was 40k and we had a 20k trade in.) they said they couldn't. We walked , went next door to another dealer. They called us back 20 minutes later with a deal.