I won't pretend to be an expert at this as I've only had to buy a new car twice but I'll offer my advice anyway. In addition to doing the required research - don't go to the dealership without financing! Go to your credit union or bank or even online and get the financing you need first. Not only will it save time, you'll know in advance exactly how much your monthly payment will be. You'll know what you can afford and more importantly you'll throw your salesperson off their game. Knowing what your payment will be right off the bat really puts you in a better position to negotiate as it takes away a lot of uncertainty and makes you more comfortable. Long story short - I once had only a few days to buy a new car (work related). The first day and a half I spent calling around/online looking for financing. I wound up getting a loan through an online lender. ($22,000 @ 7%). Once that was done I very quickly started my research. I had an idea of what cars I wanted and I knew in advance what I could afford so that helped. The check was in my hands two days later. That afternoon I deposited the money into my checking account. The next day I went to the dealership. I found the car I wanted and got the salesperson to quote me a price. This was the important part - I never tipped my hand that I had my financing in place. I asked him to give me a final price. He did so. I'm sure he was thinking he could just start tacking things on as he walked me through the financing process but I had other ideas. As soon as he began talking about financing I pulled out my check book and said, "I can just write a check to cover the entire cost today". He looked like I just kicked his dog and spit on his mother. He immediately asked me if there was any way he could convince me to finance through them. I played hardball for a bit until he dropped the price by $2,000 and offered me a 5.9% interest rate. My final price was cheaper than what I was quoted. My monthly payment was lower that I anticipated, and the interest rate was better. I was there in the dealership for about 7 hours (until 11pm) but I walked away with a deal. The salesperson dropped the car of at my house the next day. Not bad for a guy who HATES dealing with salespeople. The whole process took about 6 days. As for the original loan, I paid the entire amount back on the following business day.