Within the current paradigm change from Quality-of-Service (QoS) towards Quality-of-Experience (QoE), the question of how to charge for QoE is widely neglected in the research community despite of its obvious importance. In this paper, we present and analyze a fixed point model which specifically reflects the double role of prices, i.e. as regulating factor for demand size and at the same time as part of the QoE-based user context. The model is validated through comprehensive user trial results which allow interesting insights into the temporal behavior of end users who are confronted with a fine-grained scale of choices on video quality and corresponding tariffs.