I have money in my American bank account. I send it through Western Union to my Mexican bank account. Then I go buy dollars at an exchange house. I do this to make a couple hundred dollars every time, just as extra money.

I travel to the USA almost every week carrying no more than $4,000 every time. Every time I go into the USA I get asked how much money I have on me, I always tell them with no problem whether I have 2, 3, or 4 thousand.

Yesterday, they asked me a lot of questions and made me fill in FinCEN Form 105 which I read is designed to declare more than 10,000 USD. I filled it in for the amount of $3592. However, the officers never answered my question: How often can I bring $10,000 or less without having to report it? Is it every week? Is it every month? Is it every time I go to the USA even if I go every day?

I felt that they made me fill that form that by law I was not required to do so. Can someone give me an answer?