Modernize Secure Finance Desktop App

I’ve relied on this offline desktop tool for years to manage invoices and compile expense reports securely, but its look and feel have not kept pace with today’s expectations. The overall layout is clunky, menus are hard to follow, and several UI components are no longer supported... (Budget: $750 - $1500 USD, Jobs: .NET, C# Programming, C++ Programming, Data Visualization, Desktop Application, Software Development, UI / User Interface, WPF)