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.
This last point in my opinion is ONE major benefit you must seek to extract, if you choose to engage the services of a developer. S/he should be able to help you develop (in_house) expertise needed to maintain the application AFTER s/he is gone. If you fail to ensure this, all your cost_savings from using the application might end up being spent paying the developer to maintain the application over time in the future!
Get Maximum Returns On Your Investment In Spreadsheet Automation By Developing "In House" Expertise. Organisations can deliberately expose their employees to learning events(or self_help tutorials) on spreadsheet solutions development. Such employees can then be challenged to develop in_house solutions that effectively address the business' peculiar data analysis/report_generation needs as they arise.
One Possible Application: Plotting a pie chart based on income contributions from all your products and services(daily, weekly or monthly), and reviewing the automatically computed percentages/visual pie slices, can give very illuminating insight.