Trading in a car is easy, usually.
BTW, “trading in” implies that you want to sell your car to a dealership as part of a deal to purchase another vehicle. You can, of course, always sell the car “private party” to another individual if you choose.
0. Wait until you’re ready to deal. Markets and offers change frequently. Finding the exact car you want but being unable to take action until days, weeks, months just wastes your time.
1. Get an offer on your current car. Most dealerships will provide an offer after some cursory inspection of your vehicle. This is usually the least amount of money you can get for the vehicle as it offers great convenience to be able to get all of the deal done – that is, sell old car and buy new car – all at one time.
2. Compare that offer to your payoff amount (which you get from the bank or lending institution that is financing your car). Right now in early 2012, you should expect that on a 2011 domestic model, assuming you paid little or nothing down, chances are the dealer’s offer on your car is less than the payoff amount you owe the bank The technical term for this is negative equity. If the offer is more than the payoff amount you owe, congratulations! You have downpayment in hand.
3. If you do have negative equity, you’re not necessarily out of a deal. You can roll that negative equity into the financing of the new car you want to get, assuming your credit and other conditions support it. However, this is usually a bad idea for most folks… you’ll be working to pay down negative equity for months, even years. But if you do choose to finance negative equity, make sure you purchase GAP Insurance, usually offered by most financial institutions.
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Most dealerships try to negotiate/haggle on all of the various aspects of the deal, including the price of the car your’re buying, the offer on your trade-in, financing rates, downpayment, etc. The only way to shop around is to get all of that in writing up front, before signing any papers. Most dealerships make that difficult.