I use to work as an Application Packager
Depending on the app, it would take between 1 hour and 1 week to create a fully automated installer (MSI/MST). It would typically take 1 day. 1 week is VERY unusual (I can only remember 1 package taking that long). This included documentation and a test install/uninstall. It wouldn't include Discovery (getting the requirements from an expert user), or UAT (functional testing), as these parts would be done by dedicated teams. £6,000 is an outrageous price, but it doesn't surprise me once I know an outsourcing company is involved.
Any bets on how long it takes for Matt Handcock to get a nice lucrative non-exec role at some kind of private healthcare company?
Biting the hand that feeds IT
