You're right about any bank transaction over $10,000 having to be reported to the government (and if the money is legally yours, all is fine). But I know that people have been investigated for making repeated cash deposits "just under" $10,000.

The thing is, selling a car or something might give you a one time chunk of change, but doing it repeatedly looks odd.

When I bought my house, they checked every deposit I made and wanted pay stubs to show for it.