6.2 The costs of using assets and resources are defined by the value which reflects the best alternative use a good or service could be put to, or opportunity cost. The starting point for estimating opportunity costs is usually market prices. It is important to understand the best alternative use of an asset being valued, since better alternatives may exist. The opportunity cost of labour should include the total value of the output produced by employees. This is the cost of employees' time, based on Full Time Equivalent (FTE) costs and includes pension costs, National Insurance, allowances, benefits and basic salary.