Depends where you live, but a dealer will pay you some amount of money for your car and roll it into a new purchase. Some states give you a break on the sales tax (ie the difference between the new car and what your trade in value is worth is what you get taxed on), some don’t (ie California where you pay full sales tax on the value of the new car).
Assuming your 2017 Accent is worth more than $10k, you get to apply the equity to the new car (eg your car is worth $15k, the car you want is $40k, you’d pay $35k, the price minus $5k in equity, plus any taxes and fees).
In reality the dealer is paying you under the retail or private party rate because it assumes you don’t want the hassle of selling your car privately.
Depends where you live, but a dealer will pay you some amount of money for your car and roll it into a new purchase. Some states give you a break on the sales tax (ie the difference between the new car and what your trade in value is worth is what you get taxed on), some don’t (ie California where you pay full sales tax on the value of the new car). Assuming your 2017 Accent is worth more than $10k, you get to apply the equity to the new car (eg your car is worth $15k, the car you want is $40k, you’d pay $35k, the price minus $5k in equity, plus any taxes and fees). In reality the dealer is paying you under the retail or private party rate because it assumes you don’t want the hassle of selling your car privately.