Yes, there are govt. regulations on mailboxes. Years ago, I got tired of people running over my mailbox. So, I built one out of 8" pipe, and set it 3' in the ground in concrete on a 3" post. Had to set it with a front end loader. It got hit once, but it totaled the front end of a pickup. LOL. The post office inspector came out and told me it was illegal. Now, I have a P.O. box. I still get mail at the gate, but it is recessed from the road. Charlie