If I’m remembering right, the formula is a bit more complicated than that, at least in NY. My experience was that the regional representative (I honestly don’t remember the guy’s title... it’s been 22 years so things may have changed) had the ability to negotiate a buy back. In my case, Toyota offered me the full purchase price of my “lemon” against any new Toyota product. He also made the new vehicle available at invoice price, there was no reduction in value calculated for my use of the T100. In your case, since you decided against another BMW, I guess there would have to be some sort of calculation for the amount you’d get back. My first transmission started slipping when the truck had less than 3,000 miles on it (and was less than 3 months old) and I think that factored in to their decision. I was also without the T-100 an astounding 57 days in just under 10 months and was stuck driving an Enterprise compact car rental. I was pretty understanding until the third breakdown left me stranded on I-90 for two hours. At that point I told the dealer I didn’t want the truck back and they put me in touch with the regional rep, who was helpful and took care of the swap. The process was pretty seamless and easy in my end, I picked out the new Tacoma and the regional rep took care of all the paperwork and communicating with the dealer and Toyota finance. Once we had agreed on the terms of the swap, it took about a week to get in to the new truck. It was a long time ago though...