Here is a graph of the price of the Oculus Rift DK2 in the secondary market (ie buying from a source other than Oculus) over time. The prices and dates were scraped from eBay auctions. It is interesting to note that the premium paid for the DK2 in the secondary market dropped quickly from over $1200 to under $800 in about a week.
Don't consider outliers in your analysis. I would content that your limited sampling illustrates a basic economic principle in which the price of good decreases as the demand decreases. I would anticipate the decline down to the $400 mark when people will justify the premium for the more immediate attainment of the DK2.
Keep this up, will be interesting to see where it sits in 3 months.
Here's a third update to DK2 price in the secondary market (eBay). It's interesting to note that after starting at $1200 the price has more at less remained at around $800 since (red line). The new graph pulls from data on 287 reported sold DK2's on eBay. The red line (a kind of sophisticated moving average of the price) is a local linear least squares regression using an epanechnikov kernel. The reason for the high price is that Oculus is still not producing enough Rifts to clear the market at $350. I assume as their production ramps up and the wait time approaches zero the price in the secondary market will approach $350.
I purchased mine for $500.00 CDN over two weeks ago, however I still have a pre-order set to arrive in September and my bootlegged DK2 is dedicated to science.
Total cost of my pre-order was roughly $450.00 CDN so I justify that $50.00 premium as saving me almost 2 months of waiting.