Well, you'll realize a $30,000 hit in depreciation on your '2014 if you trade it it. You're at the end of the steepest part of the depreciation curve on it right now. Over the past 4 years you've lost a ton of equity in the car due to depreciation, and the smart move, moneywise, is to drive it for another five or ten years. If you don't sell the car, the depreciation doesn't matter...but if you trade it in, you will realize that $30,000 loss. Most of your loan repayment, at this point, is principal, so you've already paid most of the interest on that loan.
Furthermore, you will have a new five or six year loan on the new car, so you'll pay another $10K in interest on that car. Oh, and by the way, you'll take a $10,000 depreciation hit the minute you drive the car off the lot. And...since it's a 2018 vehicle, it will be a model year old in another couple of weeks, so it will take another immediate depreciation hit.
You're getting screwed, financially, on both ends of this deal.
Now, I don't know your financial situation, or whether your current Q7 is old, tired, broken, all scratched up, ash trays full, etc. If you can write the car off for business, maybe the financial damage is less severe.
Me, I like to buy cars at when the depreciation curve starts to level out. Bought our '10 Touareg TDi 3 years ago at less than 50% of original retail. Buying the replacement '13 Q7 at 1/3 of original retail. Bought my '04 allroad 4 years ago at 5% of original retail. Yea, the cars aren't quite as shiny, and we pay a bit more in periodic maintenance, but we don't have a $700 monthly payment on any of our cars....
Others will have their own opinions. :)
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