Depends on what the dealer decides on the trade-in value of the car. They have to make a profit on the car you're trading in so most likely depending on the car you're trading in expect to hear somewhat of a lesser figure than you expected. Go in, see what they say. If it's less than what you expect then better off doing a private sale if possible. And no it will not reduce your interest rate on the lease. This part comes down to how nice your credit looks out there. Good luck with the venture and feel free to ask more questions I am sure others will be glad to guide you in the direction you're looking to go.I have a question regarding leasing, I have a car already that I would like to trade in on a lease, the car is already been financed and paid for but, i would like to lease an IS-F. Will trading a car on a lease, reduce the tax percentage? or is that only if you trade in on a purchase/finance?