That's alright since the credit card company is the one who'd be filling out the form - you'd only need to fill it out if it was a private transaction between t

That's alright since the credit card company is the one who'd be filling out the form - you'd only need to fill it out if it was a private transaction between two natural persons - and even then only one form needs to be submitted so if it's someone who regularly engages in such transactions (like some kind of service worker) then they'll probably submit the record of it assuming you insist on paying with cash. Nearly all of this sort of reporting is generally carried out by banks and credit card companies that are being used to execute the transaction - but the US really does want to know if you purchased a used car from someone for 13,000 dollars in cash since, you're probably laundering money at that point.