No. of Recommendations: 4
Anecdotal, but interesting.
I used to be an Ebay power seller, long ago. I will use it to check the real value of a whatever - completed listings are a good honest arbiter of what something is worth.
When Apple has significant hardware releases, like I would say the Duo is, you'll see a significant price spike for what these new shiny items go for right after release.
Checked today and many completed listings for the Duo at the $9k or so level. One was for $9777.
Amusingly, when the iPhone 6 was released in 2014, it sold for $10k right after release in the secondary market. (I made a screen grab of that expensive ass auction result, and used it in a finance class I was teaching at work, to indicate that delaying gratification will save you a lot of coin). The 6 was was the first "big" iPhone.