"Every scout under the sun is watching Cardiff at the moment and every player has a value," Ridsdale told the Western Mail.
"I expect people to be knocking on my door, but they can knock as much as they like. Certain players have a value and that is that.
"Every player is up for sale, that has always been the case. What has changed is that the price has just got bigger - it would take a massive cheque to prize certain players away."