I take Hack #1 with a grain of salt. The more important thing is to know what the car is worth and what you're willing to pay. You might be able to find a deal on craigslist, but you can also negotiate with dealers, and they often inflate the sticker price. I bought a used car recently. One dealer was overcharging and rejected my offer so I walked. I ended up negotiating hard and got a better deal elsewhere. Also, do your homework. From the timestamp on the google cache of an online isting, I knew how long the car had been on the lot. This turned out to be a useful bit information during the negotiation.