Wow, more good points.
Suggestion: call and talk to a Tesla Owner Advisor *today*. Issues:
1. Can you put down a $2500 deposit by the end of the year to secure a CPO, new build-to-order or new inventory car, to be named at a future date?
2. Does putting down your deposit now guarantee that you will receive free lifetime supercharging?
3. Can you get your deposit refunded if you decide to buy privately instead?
4. In a private sale, will you receive (these should all be "yes", you're just checking):
a. balance of existing warranty
b. transfer of any extended warranty
c. free lifetime supercharging
d. do any of these answers change for an S60 or any other previous or current model?
5. If you're getting pretty close to a car config you want (e.g., S75D, 2014 or later, AP1), ask if the OA can look up to see what he/she has in inventory that might be a close match. I love ev-cpo.com and look at it often, but still wonder whether Tesla has some inventory that isn't visible to outsiders.
WRITE DOWN THE ANSWERS. Send your notes in an email to the Owner Advisor and ask him/her to confirm their accuracy. There have been, um, disagreements in interpretations in the past from different OAs at different sites. You need a written record to point to.
One other suggestion: buy a 2014 or later. I had a 2013 P85+ that I loved. And I miss it even now.
But I traded it in for a 2016 model partly because the 2012/2013s have garnered a bit of a reputation for a slightly higher issue rate. ALL of my issues with that car were taken care of promptly and lovingly by Tesla service, and with your CPO warranty you'd be in good shape, but if you're relying on the car every day you want to minimize down time. I don't have data to back up my assertions, but based on anecdotes on this website, strongly suspect that the 2014s and later have had some fixes put in that ups their reliability.
Best of luck,
Alan