What similarities/differences did you find between this design and the design process you underwent for the Customer Service project?

I have just finished C# course and a project for calculator. In order to finish the design project, it needs to plan very well, set up technique requirement document and dead time. Just like customer service course we need to undersatnd client's requirement and set up dead time. In the design process there is nothing to do with money. while in customer service the one of main issue is about money. To finish design project, the requirement document focus on every detail: like how to operate properly, how to handle user improper operation. In all, the the document set up the design target and target scope.
For anykind of language, if we understand the requirment, and break down the problem into relatively small independ pieces, and follow the programming good practise, the taget can be reached whinin resonable time.