Ok here is what I can advise, pretty much what had been said already. Know what you want, do not spend a second being pulled between different models and trims, this is time consuming and will pull on your patience and judgment. Do not think these salespeople know how to play you when you have been there 3 or more hours and are hungry or tired.
Know the ins and outs of the car, don't know it is such hp or this quality/safety rated. Know why the engine type is different, know what plants build the car. Get to know some of the detailed features of the car, what the systems and acronyms and the various technology trends that each brand calls something different but are in principle the same. Research the hel out of it to the point you can tell the salespeople things they did not know, it will throw them off if you ask some questions they do not know the answers to.I did this in the negotiating cars and if you pick a point they are a bit dull on you can turn it on them and kinda create a arguing point to get them to change their stance.
Look of course at basic things like dealership cost, yes you can go below that but look at it in reason.
Research message boards and look at WHAT OTHER PEOPLE have ended up doing, their prices. This is a great way to look at realistic view on how far you can negotiate down.
If they say something like "I have only this selection to choose from" tell them you wanted a cheaper trim and they will drop the price of the built up packaged one to the level that you wanted i.e. cheaper.
CHOOSE A HIGH VOLUME DEALERSHIP! Get a salesperson that sells a ton of cars these things combined can get you already a break on prices.
When I was buying my mom's car we went to a lot of dealerships, there were 3 or 4 tiny ones that I would say a starting point and they just said "no way we can't do that". It is because they only sell to a limited area or a specific type of customer, i.e. a lazy uninformed or impatient one. There are some that you research their sales rates or just know that they are the "big dog" dealerships that you can see they DRAW a large consumer base from. People will travel outside their areas 30 40 100, 300 miles to go buy from because they know the type of price break that the high volume dealership can give over others.
BE PATIENT omg if you go into this like playing a 9 hour poker game and read to react properly, guess what you win. This is pretty much a game of attrition be prepared with the right tools, usually distractions are things you need to not be focused on such as another person with you(depends on who I guess) or being fooled by their complicated presentations i.e. documents on payments or choices or detail overloading. I had one dealership try to explain to my brother (he went in on one negotiating and I observed and they told him how they were taking away options and actually charging more. Of course that was obfusticated by the double talk lawyer type speak, I interjected talking over him "ok know this is what he took out, this is the price, that is the result". I just spelled out what he did in simplistic terms so that it was apparent instead of kinda confusing.
Well I won't bore anymore just try to do a decent job, you might not reach a set goal but in the end you will be happy.
