ERP software

I am looking to get an ERP software developed for a building,plumbing merchant business, for windows environment. it needs to take care of all business processes for example: EPOS,stock control, customer accounts(CRM), sales order processing, invoicing,purchasing,warehouse management, despatch(courier integration), e-commerce integration, etc.. to get a better idea of feature-set I am looking to implement take a look at http://www.orderwise.co.uk. As you can see this is a substantial project and I need serious programmers. Please only bid once you fully understand what is required and please detail your experience in your bid.