Calculate disaster recovery cost vs RTO/RPO targets. Lower RTO (faster recovery) and lower RPO (less data loss) require more expensive solutions: hot standby > warm standby > cold standby > tape.
Enter the values for the scenario you are assessing. Calculate disaster recovery cost vs RTO/RPO targets. Lower RTO (faster recovery) and lower RPO (less data loss) require more expensive solutions: hot standby > warm standby > cold standby > tape. Use the rto vs rpo tradeoff result to inform your calculation.