I need a complete, working business suite that covers Accounting, Sales, Inventory, Invoicing and Personnel Payroll. You may deliver it as one integrated application or as clearly linked modules, provided every part runs reliably on its own and shares data smoothly. Accepted languages are Python, C or Visual Basic .NET—choose whichever you already master. What matters most is that you hand over the full, well-commented source code, a sample database, and clear build/run instructions so I can compile or execute everything on a Windows machine without extra troubleshooting. Typical flows should work out of the box: inventory updates after a purchase, receivables after a sale, payroll entries posting to the ledger, plus standard reports such as trial balance, income statement, stock movement and employee payslips. A clean, menu-driven GUI is enough; flashy design is optional. Deliverables • Source code for Accounting, Sales, Inventory, Invoicing and Personnel Payroll • Executables or build files ready for Windows • Script or notes for database setup • README or short user guide with sample credentials Acceptance criteria: I compile or run the project locally, open each module, perform basic create-read-update-delete actions and generate at least one report per module—with no runtime errors. Existing codebases are welcome as long as you own the rights and can adjust field names or labels if I request minor tweaks.