11. Overheads for PPP/PFI contractors are likely to be low as many do not have a large company structure to support. However, this may not be the case for all contracts. Commercial staff should endeavour to agree the approach to overheads with individual contractors to prevent the need to debate the issues for each change. Although it is unlikely that it will be worthwhile, or appropriate, for CAAS to agree overhead rates annually with the SPV as is done with other contractors, advice can be obtained from CAAS on a general agreement of overhead rates to be used. In some cases it may not be appropriate for any overheads to be applied to work undertaken by the SPV.