Here's the situation, we love our Model S but it's getting a bit older and starting to have some out of warranty repairs. We love the Model X for a variety of reasons. My wife, who much prefers the look of the S, has finally conceded that the X is more functional and has warmed up to the idea of trading the S in on an X. Here's the good part. She's a consultant who operates under her own LLC and who drives a TON of miles tending to her clients. Using the X for business use 100% of the rest of 2018 and 95+% of it from then on for the rest of the life of the X is a certainty, so we'd be looking a great tax incentive for buying the X now. Money is absolutely not a problem for us in buying the X, either. Nor are we concerned about an audit because we have a great accounting firm doing our taxes and her business use of the X is completely above board without a bit of imaginative interpretation. The problem? Even with the tax incentives, our net cost on the X we've configured is probably around $75k, all said and done. We're about five years away from our planned/hoped retirement date and I'm suddenly thinking that, as cool as the X would be, I'd just rather add the money to our retirement instead, not because it's a necessity, but just because more options, freedom, and possibilities when we retire (and maybe retiring a tad early) is the better thing to do. Having a more fun car to commute in now suddenly doesn't seem as desirable as the ways in which the money will possibly enhance our retirement. My wife is okay with switching to the X but is equally keen on the idea of padding our retirement by another $75k (more with growth, insurance savings, etc.). Even with a few thousand here and there keeping the S going for another few years is a significant savings over switching to an X now. I'm a logical, numbers type person but his feels more like a philosophical decision than a financial one, so I'm struggling with it. And I can't believe I'm even thinking this after spending nearly a year convincing my wife that an X is more functional than an X. Aaaahhhhh!