Recently, a new paradigm named cooperative cognitive radio networks (CCRNs) is proposed by many researchers to realize cooperative communication and cognitive radio technologies. In CCRN consisting of primary users (PUs), secondary users (SUs), and the secondary AP (SAP), the leasing and pricing of spectrum bands and cooperative spectrum sensing is occurred and SUs relay packets to get the temporal spectrum permission. These behaviors can be modeled by using multi-stage Stackelberg game, and some previous results are already available. However, since existing CCRN studies did not consider spectrum pricing, we propose a new CCRN model which SUs' cooperation is coordinated by SAP to reduce leasing cost, based on a simple multi-stage Stackelberg game. Our preliminary result shows some distinct characteristics of CCRN which affect the optimal strategy.