1. 
   On costs
   costs of establishing a presence on site, site huts etc.
   Found op http://www.encyclo.co.uk/local/20935
   
   
2. 
   On-costs
   On-costs:
   Found op http://www.bplans.co.uk/glossary/index.cfm?a=s1&sterm=On%2Dcosts%0D%0A%0D%0
   
   

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