I disagree. KFNC is exceptionally bad. It is the worst commercial fm rimshot in the market. The booster isn't helping matters west of downtown.
As far as the price, I think KHJK went for exactly 5 Million while KFNC went for a bit more. But of course that is from memory, so you could be right.
Back in the day, KFNC outperformed KHJK by a slim margin. This was when both sites were well maintained, their transmitters tuned for minimum AM noise, etc.
From a technical standpoint, the sites are nearly identical. I strongly suspect any advantage KHJK has over KFNC is a matter of paying attention to details like keeping AM noise to a minimum, making sure the transmitter is at full power, etc.
Agreed on the booster. That idea has been kicked around and tried by a few other rimshots here, all with no success.