Fixed price covers one module: one user role, CRUD on one directory or document, and export to Excel.
I turn your one-page requirement list into a working shape (who works with what rights, what we store, which printed forms are needed); write the app on C# / WPF over MySQL: login, roles, directories, stock or orders, activity log; check rights inside the services, not only by hiding buttons; send an interim build every 3-4 days so the result is not a surprise; hand over installer, sources, database dump and README with run commands.
You get the installer, the sources, a DB dump, the README, and a run log with screenshots of the scenario new user, item, order, report.
Not included: the second and later modules, mobile or web version, sync with external services, migration from old databases, user training, edits after two revision rounds.
Delivery: 5 days per module. The full contour from a spec is a separate order.
What I need from you: a one-page requirement list (who works and with what rights, what we store, rough row volume, printed forms, where the database lives); Windows version; access to the database server or permission to run it locally.