Minimum wholesale value is around $20. They decreased much these days, but now the prce is stagnating.
Of course this one refers to the worst letter combo's. All premium ones (without QWYUJKZXV) go for a minimum of $220 or so ...
I got a bit more than 100 of these, and the best place to monitor their prices continually is the name*pros short domain discussion forum or on 4*letter*noob*com (remove or replace the *'s).
I would advise you to hold onto them, if you got some. The renewal time is mostly over (for the worst quality ones) and the prices will slowly rise imo (but don't expect any big rise).
SH