The P&ID's for our industrial complex need to be updated every time we implement a change in the field. These are typically small changes - such as inclusion of an extra valve or insertion of a control loop. Drawings are maintained in AutoCad and updates to drawings need to be made, checked and approved. Approx 100-200 individual changes per annum. Am interested to hear if you would be able to provide this service and how much you would expect to receive in return.