Lease versus buy
That is a personal decision that you need to make based on how many miles you drive and your finances. Be aware that if the car is not pristine when you turn it in there will be large charges for any things that need to be repaired. I personally would not lease a car.
I've always buy my car but personally its because I drive a lot.
My suggestion to you would be to negotiate the best possible deal and then buy the car outright for CASH, if you're in the position to do so. But if you MUST finance the purchase, do so OUTSIDE of the dealership, and for the lowest interest rate possible...even 0% interest on a home equity loan. Why? Because the dealer will always try to leverage the price of the car against the interest rate on any financing.
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