That's pretty good, but I picked up a 2014 P85+ similar config to yours in Black in May for the low ball price of $39K, or ~$42k out the door. Seems about $7-9K too high. Same mileage as I had.
Check the following:
1. Taillights; for Fogginess or LED's fading or out
2. CF spoiler finish; mine was worn down on the protective coating, looked like crap, replaced with RPMTesla version
3. Test drive, listen to motor noise. Two things, clicking sound on acceleration or regen engagement, noise indicates "splines" need lubrication. Motor noise, and I mean noticeable on acceleration, not a simple whir, but loud perceptable sound indicates a failing DU
4. Check the displays for yellowing or bubbles
5. Check interior trim that Tesla won't fix under warranty or due bill anymore
6. Check battery rated range at 90% and 100%
Mine i think was marked down for:
1. the taillights failing: replaced under warranty after purchase
2. Motor noise, it's taken 6 months by the spline noise and loud whir got me on the replacement DU list finally
3. sunroof roof rack cover flap missing
4. Center console missing the cup holder inserts
5. one key. I mean really 1 ****ing key? Cheap ass Elon
btw...my 100% is ~252-254 rated range
