Just trying to make sure I understand this. I think there are three price comparisons:
You’re valuing the additional capabilities of EAP (vs the current AP included with new cars) at $4k based on your ‘$2k discount from FSD’ above. From this article (Tesla (Enhanced) Autopilot vs. Full Self-Driving: What's the difference now?) those additional capabilities are (1) auto lane change (2) autopark (3) summon (4) navigate on autopilot. That gets to the $50,100 new car price you have above. If we include the additional PA sales tax on this just-for-illustration EAP new car (on $53.9k vs. $47k) that adds $414 to the new car so call $50,500 the new car comparison price. So at $47k you’re giving a $3.5k discount for 6k miles of depreciation, 6 months less warranty coverage, and having another owner in the vehicle history. Again, assuming the EAP extras are worth $4k to a buyer.
If they’re not, buy new and pay $49,900 + $1,200 - $3,750 - $1,250 = $46,100. Plus an additional $174 in PA sales tax (on $49.9k instead of $47k). So call $46,300 the new car comparison price, assuming fed and PA rebates.
And the last one (getting your car to FSD vs a new car with FSD) is what mswlogo posted. At $47k + $5k for FSD, your price is $100 less than a new car for a buyer who qualifies for the fed and PA incentives: $49,900 + $6,000 + $1,200 - $3,750 - $1,250 = $52,100. Include the additional $234 in PA sales tax (on $55.9k instead of $52k) and call it $52,350 vs. $52k for yours.
I’m using -$1,250 as the PA rebate as you did (since it’s taxable income). I don’t know if the $1,200 dest and doc fee is taxed; if it is add $72 (or $100 for easier math) to all the comparison prices. Did I mess up anywhere?
That's a lot of math, looks good but you're missing the home link, NEMA 14-50, missed opportunity of having money tied up for 12 months, and the people who simply can't front an extra $5,000 for a car, to get a rebate a year later...
The good news is 7/1/19 the comparison to new will change drastically, and the PA rebate is only good until they run out of money.
The bad news is I still don't have a VIN for my X.