They are insanely high on Ebay, maybe they thought they could get more? I dunno. I might have been looking at the wrong item. I just checked the site and it says:
Antminer S9-13.5TH/s
Shipping: March 1-10,2018
2320 USD ( 0.16888080 BTC; 0.94561364 BCH; 9.88517011 LTC; )
So yeah, $1000 over old prices. But still, it's half what they want for the Avalon on that site. Crypto is always higher than Minerwarez, so I will wait and see what they offer them for. I might just stay at my hash rate if they are (in my mind) too costly and 4000 is too costly for my tastes.
Yes, miners are becoming quite expensive. If one mine with the intention to convert BTC to FIAT as the reward comes in then one may need to rethink the strategy.
We have to use some calculations to justify buying miners I suppose (or take a leap of faith). On my calcs and some scenario (which will be wrong):
With an average network diff increase of 5%-12% per 2016 blocks over the next year the cumulative BTC return after 12 months will be 0.01452 to 0.0251 BTC/1Th. (Excluding tx fee and pool cost)
A scenario: Say for 12 month period accumulate BTC reward :
12% diff increase avg. => total BTC=0.01452/Th ; BTC/$ 'double' to $29000 => Return $421/Th
Avalon821 at 11Th/s => Return $4633 after 12 months.
Antminer S9 at 13.5Th/s => Return $5686 after 12 months.
A lot of ifs and maybes but not sure I will buy an Avalon821 at $4000 (excl. tax, shipping, running cost) if want to convert to FIAT within 12months.