As someone who just pulled the trigger on a new 60D (is it here yet?), I'll offer my slightly different approach. To me, this purchase was not a normal car buy decision. Perhaps I've fallen prey to Tesla's marketing, but what I'm buying is both a car and an experience. I'm buying a new hobby. I'd always had my eyes on Tesla the past couple years, am still skeptical of Elon Musk, but then I got behind the wheel of one a couple months ago (X 90D). Game changer for how I could drive and how it made me feel.
As a fellow finance guy, the numbers aren't going justify the 60 just like they aren't going to justify a P100DL. The entry price of new is already crazy, and of course you'll take a depreciation hit. Things that slow that hit are AP2 and recent facelift, meaning we probably won't see anything too revolutionary in the next year or two which would render late 2016/early 2017 cars wholly inferior. The 2014 AP1 cars carry more value in 2017, and I expect the same to hold true in 2020+ for recent purchases. The advice earlier in this thread about CPO is valid as well, but ultimately I decided on new because, "If I'm spending over $65 or $70k on a car, I shall get exactly what I want."
My order (is it here yet?) is just over twice what I've ever spent on a car. Options I wanted and why outlined here:
-60D - last minute decision to get AWD was more about acceleration than any need for AWD. Something about the lyric "0-60 in 5.2" from the old Alabama song "I'm In A Hurry" struck a chord with me. Not a finance decision. I could also afford the 90D comfortably, but there would be so few times I needed that kind of range that I could not justify the extra ~$20k. Based on the recent battery studies shared on this forum, 75 or 75D was never considered. Almost no value to me.
-Black - I genuinely wanted this color.
-All Glass Roof - Purely a feel decision. Why would I get my dream car and not have a wide open feel? I am moving from a pickup truck to a car, so I'm already sacrificing some visibility. Once I sat in one with the all glass roof and saw it was "only" $1500 more, it was a no-brainer.
-Tan Seats - For whatever reason, I can't imagine a luxury car without leather seats. I've always liked the Black/Tan combo. I considered the all white "vegan leather" option, but I worry about keeping them clean and how they might discolor over time (my own speculation).
-PUP - I was really on the fence with this option. For $3500 I don't find this to be a good value. The tipping point in favor was the ventilated seats. Even though folks have complaints, the Texas heat is a 9 month affair each year. I think a car in this price category should have this option. I ordered on the night Tesla removed this feature from the PUP and was able to confirm I'd receive them. If no ventilated seats, I would've skipped this option.
-AP2 - No-brainer decision for me to include this option. I wouldn't have bought one without it.
-FSD - I actually considered not including this option and upgrading at a later date, even if a little more expensive down the road. I think we're 2+ years away from meaningful application, so why should I give Tesla $3k in venture capital? Well...I want to have it when it's first available. Not a finance decision.
-Air Suspension - Skipped this option as I didn't think it would be used very much. I also speculate about higher maintenance down the road with an added moving part.
-Sub-Zero and HiFi - Neither of these are important to me, as I live in Texas and am not an audiophile who could tell much of a difference. If ever I want a sound upgrade, there is no shortage of aftermarket options.
The long-winded conclusion for me is that the entry price is not financially justifiable. If you can afford it (and you indicate you can comfortably), the decision to buy is about feel and experience. In my opinion, the upgrades from the entry price shouldn't be treated as solely a financial decision when framed in the context of a purchase which doesn't make financial sense. Get the options you would appreciate and ones that would enhance your experience in the car. Isn't that why you're buying it, after all?
End of rant (is my car here yet?).
