To have an equivalent level of certainty in such a model, there would need to be a fully worked up definition of how the model would be implemented, stating where the boundaries of risk transfer would lie, with assumptions regarding the private sector's response to the brief.Consequently, for the purpose of this initial assessment of the PPP Private Build Public Operate Option, PwC's approach has been:(a) to consider in conjunction with SPS the key issues of risk transfer and operational interface involved in implementing a PPP Private Build Public Operate Option and the implications of these for the definition of the PPP Private Build Public Operate Option and for its deliverability;(b) to undertake an outline financial assessment of the PPP Private Build Public Operate Option based upon scenario analysis of possible financial outturns relative to the PPP Private Build Private Operate and PSC options.Para 4.6.5:Unless the PPP Private Build Public Operate option is more fully specified it is not practicable to develop cost estimates which provide significantly more accuracy than the scenarios outlined above.In addition, the report also concludes in para 4.6.5:However, the above analysis demonstrates that any PPP Private Build Public Operate model has a very substantial value for money gap to bridge compared with the PPP Private Build Private Operate option and also a requirement for major changes in the approach to prison operation and staff terms and conditions within SPS to reduce its costs significantly below the PSC.