Well DHL now has all the info they need to steal my identity.
I guess when you import something over a certain dollar amount they require your SS number and proof of address. They had me send a pic of my SS card and I threw in my license. I bet the fact that I live at a business was also kinda weird to the customs people. Apparently asking for the SS number is normal, I did look it up before sending it and it was the DHL website but it's still always weird giving up that info.
My last watch (surprise, also a Square) was shipped from Japan but it was like $450 total and there were no customs issues or requests at all.