Typically in the USA, one would sell for $2700 - $3500, it depends on the number of actuations and condition.
I'd not hesitate to pay $2700 rather than $1800 for a 7D MK II. Don't fall for the early hype. I had to sell my 1D MK IV because of problems with my hands, but it outperformed my D800 in a side by side use at a theater event, two different shows, actually. I tried my 7D at one, it was hopeless, gaining 1 stop in raw would not help.
Canon rates the high ISO on it using jpeg, looking at raw files, its the same as the 70D. Tale a look on Imaging Resource at high ISO's on different camera models. I look at the yarn hanging on the wall, and compare detail, contrast, and color saturation. The 1D MK IV has lots of detail and contrast at ISO 12800, not so the 7D MK II. I'd give the 1D MK IV a 1 stop advantage. A 6D has about 1-1/2 stop advantage.http://www.imaging-resource.com/IMCOMP/COMPS01.HTM