It's rare to see a used car sell at a higher price than what people could pay for a new one, but that's exactly what's happening with the Tesla Model S.
According to iSeeCars.com, a search engine that helps people find used vehicles, the average used Tesla Model S last year sold for $99,734. That's well above the average MSRP for a Model S—which typically ranges between $71,070 and $94,900—and average transaction prices, which come in at $93,000.
The survey analyzed 45 million listings for vehicles sold in 2012 and 2013.
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"The Tesla Model S is still just a sliver of the used electric car market," said Phong Ly, CEO and co-founder of iSeeCars.com. "However, it seems to be in great demand, as used Model S vehicles are selling above its new car price."
The majority of the used Model S sedans sold last year were the higher-end versions with a bigger battery pack, according to iSeeCars.com. Those include the 85 kWh Model S and 85 kWh Performance Model S, known as the P85. The average MSRP for a Model S P85 edition was $106,000, while the average used model sold for $107,000, Ly said.
It's not hard to find used P85 Model S vehicles listed on auto websites for more than $100,000. On AutoTrader.com, one with 6,841 miles is listed at $109,970. Another Model S with 2,200 miles is listed at $114,587. The lowest price on AutoTrader.com for a used Tesla Model S is for a 60 kWh vehicle with 13,372 miles, which is listed at $84,888.
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Ly said it's still hard to determine exactly what is driving those selling used Teslas, and why those buying used are willing to pay more than they would for a brand-new vehicle.
"It may be that some people do not want to wait one to three months for a new Model S," he said.
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Meanwhile, shares of Tesla surged to a new all-time on Monday. The stock traded above $199 for the first time ever, with many saying they believe its momentum has returned ahead of several important milestones.
These include delivery of the first Model S vehicles in China, the announcement of a new "giga factory" to increase production of lithium-ion battery cells, and the upcoming release of fourth-quarter earnings on Feb. 19.
The stock has rallied more than 60 percent since slumping to $119.52 in November.
—By CNBC's Phil LeBeau. Follow him on Twitter @LeBeauCarNews.
Questions? Comments? BehindTheWheel@cnbc.com.