A key component of my process was, after saving them a truckload or two of money, I would rigorously document what I did, how much we saved (metrics METRICS met

A key component of my process was, after saving them a truckload or two of money, I would rigorously document what I did, how much we saved (metrics METRICS metrics), future places we could employ the technology/technique/whatever, etc How do you generate the difference between the project that you got done with your method versus the project that wasn't done using a different method? Is it real cost of your way versus estimated cost of doing it the other way, are you re-writing a project that has already been written by a different team, or what? If the cost of the other way was an estimate, are the metrics trusted because you have a great track record with your estimates, or do you have some sort of estimate-aiding tools that your employer relies on and trusts?