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.
The savings _ from using your "in house" expertise _ in terms of money and man_hours alone, will quickly justify the investment you make in "developing the needed skills" _ especially, when you compare what you spend with the cost of purchasing a commercial software application _ or even engaging the services of an Excel VB developer.
I believe using either of these two applications should not pose any problems for implementing your spreadsheet automation ideas. This is because both have always been "friendly", towards making it easy for users to get more functionality out of them by way of custom programming.
From this point on, I will refer to only one of the above mentioned applications, because it is my preferred work environment. That is Microsoft Excel. I believe users of other spreadsheet applications will be able to adapt whatever I say from here for use in their own peculiar environments.