Your data is a file you own
One SQLite database in your user folder. No account to lose access to, no server to depend on, nothing to cancel.
Backups are a button, not a procedure: the app writes a consistent copy while it is running, keeps as many as you tell it to, and can also take one automatically when you close it. You choose the folder — an external drive or a synced folder both work.
Restoring is equally boring, which is the point. Pick a backup from inside the application, it checks the file really is a BasicInventory database before touching anything, and puts it in place. A copy carries your settings and your licence with it, so a new computer is a restore rather than a re-setup.
Every list exports to CSV that opens straight in Excel with the filters you applied, so leaving is never a hostage situation. And uninstalling asks whether to delete your data, with “keep” preselected; your backups folder is never touched either way.