Для общего развития имхо достаточно почитать статьи на эту тему.
Вот интересная ссылочка
http://www.nucleusresearch.com/research/f64w.xls
Цитата:
This workbook has been developed to evaluate the value of a Microsoft Business Solutions - Axapta technology deployment.
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Calculations such as return on investment (ROI), total cost of ownership (TCO), payback period, and net present value (NPV) are calculated and may be used to either select the best solution or negotiate better terms on a solution that may have the wrong cost structure.