The way it's looking, except for the transmission, you have addressed most of the troublesome issues.
Program Car = Rental Car. Can you imagine how that car was treated before you bought it? The Taurus was probably one of the most popular with the rental car company's, and the market was flooded with lease return's which caused the book value of the Taurus to take a nose dive.
It's a lose/lose situation, do you take a loss to keep it or take a loss to sell it.
In my opinion, I would probably hang on to it. Maybe it will treat you right for awhile. But keep in mind, the transmission is the weak point of the Ford Taurus.
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