Custom spreadsheet solutions which survive long after the developer has "left the scene", are often those which users accept because they discover it _ among other benefits _ makes their work quicker and easier to do. That is why the best person to develop such solutions tend to be one who works in that area, and is therefore familiar with the way the manual system operates. S/he would have an "insider's" perspective of the best way to introduce automation other users will readily adopt _ even as it solves the identified problem(s).
1. The Pareto Principle _ Using spreadsheet tracking, you can easily apply the Pareto principle in deciding which of your income sources and expense channels(i.e. products and services sales) to focus on in order to maximize profits. Considering that you are most likely to use the same marketing/sales resources to serve your customers, it only follows that if you focus on your biggest margin selling products/services, you will get increased profits at more or less the same cost.
Deciding What Spreadsheet Application To Use. This would ultimately be up to you. The big "fight" has always been between Lotus 1θι and Microsoft Excel. I started out with Lotus 1θι back in 1993 and learnt Lotus Macros programming(via self_tutoring). I eventually used this skill to develop _ in my free time _ various custom spreadsheet solutions(that were formally adopted for use in the departments I worked in as a brewer/manager in Guinness), before switching to Microsoft Excel in 2001. Subsequently, I developed my Excel Visual Basic spreadsheet programming skills (also via self_tutoring), because the company had chosen to adopt MS Office during the roll over to year 2000.
I am keen to encourage individuals and organisations to explore using advanced MS Excel formulas and functions, in conjunction with Excel VBA programming, to develop customised spreadsheet applications that will solve typical problems end_users encounter daily in trying to record/analyse data and generate reports.