Welcome to the "looking to buy a P85D club!" I have been pouring over the forums for nearly year and keep a very close eye on the CPO inventory, eBay, and cars.com. The present CPO P85D inventory pricing makes little sense so if you are looking to buy one be very careful what you buy so you don't overpay. The pricing they set sometimes has little relevance to what the market will pay. The price difference might have something to do with what they bought back the car for -- not necessarily how much it is worth now. They are actually trying to sell a 2014 P85D for $90K
85 kWh Performance Model S 5YJSA1H21EFP63283 | Tesla
A bunch of the other P85D listings are also overpriced and they have been for sale for months with no one buying them. Reminds me of the P85+ inventory a long time ago where they had dozens of inventory cars priced so high no one bought them and then all of a sudden they were available at a price the market would pay and this is likely what will happen to the P85D inventory.
Over the weekend, I missed a P85D that came on the market for $54,500 so reasonably priced options are out there. There are still several available for the 60s. Good luck with your search! If you find one in the 50s or early to mid 60s, save it for me.