Take a look at this web site and consider whether it would help you or not (you need to pay their fee to get all their info on a particular vehicle).  It helped me on my purchase a few years ago.  This is generally for new vehicles.

 

http://fightingchance.com/

 

The gist is that dealerships need to hit certain sales marks to qualify for higher levels of rebates from the manufacturer.  A dealership on the verge of hitting the next sales mark is going to be more apt to cut you a deal to get there especially toward the end of the month when time is on your side.  Though which dealership is NEEDING the sale the most is not usually readily apparent.  The process outlined in their guide helps you flush out which dealership(s) needs your business that month the most. (it won't be the same dealership every month) You have to be willing to possibly drive out of market to get the deal.  I ended up getting my last vehicle in New Smyrna Beach and ended up saving over $4k off of sticker which ended up being about 10%.  The guide tells you to send out a specifically worded email on a specific day of the month to 10-15 dealerships that carry the specific vehicle you are looking for.  A third or half may respond and you will end up having those that do bid for your business.  Those are the ones on the verge of the next sales goal.  You're also doing this without having to step into a dealership to negotiate.

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