Reliability of Cost Information

- Main Cost imformation is obtain from the contractors prices which is subjected to consideration variables : * From Contactor to contractor * Project to project * District to district * Over a period of time - Must interpret the cost in appropriate context before use - Necessary to know condition surrounding the prices Factors for consideration * Size of project * Climate of industry * Stability of material prices * Availability of labour and material * Whether fixed price ender * special requirements as to speed * Method of pricing preliminaries * Location of project * Type of contract - Cost information used by Qs is obtained from price BQ and it is advisable to use average prices rather than lowest tender . - Skilled judgement is necessary when extracting and using cost information - Lack of coincidence between the unit of production cost and design cost account - Prices different in bills rates are not neccessary due to mistake s in estimating - Dicculty of predicting the operational times , and regional difference and etc . - Unit cost is made up by standard cost within determine parameter - Additional cost due to specific design and abnormal requirement are in forecasting stage .