Market manipulations are a sure way to get in trouble down the road. I have been a staunch advocate of letting the price of the car reflect the supply and demand of the car in the generally free market. I definitely do not condone what Musk is doing, but I understand his perspective in trying to promote his cars and keeping current owners happy.
My take on his "guarantee" is only good for reasonably mileage cars and for only 3 years. Afterwords, it will fluctuate depending on the market. So for 3 years, you are sort of guaranteed a high price car, but after that, who knows. There have been cases when owners here have complained about low balling from tesla for their less than 3 years old trade ins.
Where is my proof of market manipulation? Well:
1) One is the 3 years price buy back guarantee. Without it, I am sure teslas might be worth a tad less than what the CPOs are going for now.
2) Two, because of this guarantee, some owners somehow feel they should be driving the car for free (or even make some profit) for 3 years if you factor in the government rebates. I have seen tesla on craigslist that have been renewed for 6 months or more now, ever since the AWD announcement.
3) Three, if you look at the CPOs lot across the country, many have shown hundreds of cars sitting there on the lot. I am 100% sure not all of them are on the CPO website. I think tesla is making sure they have around 200-300 vehicles sold at anytime on the CPO website to cap the supply. However, I conjecture they probably have close 1 to 2 thousands total sitting idle on lots.
My point is Tesla is definitely manipulating the resell value of the Model S to keep those promises to the early adopters. Again it might work in the short term, but I can guarantee you they will get themselves into trouble down the road. Think when tesla releases the model X and more flood of Used model S comes in. Think when in 2016 or 2017 when the 3 years guarantee runs out for those 2012/2013 Model S? Think when other manufacture release alternatives and somewhat lowers demand for the Model S. All this will point to tesla adjusting the prices of the used tesla to move them.