I personally have a UPS box that is called a suite #.... They will accept pacakges sent to my address when I am away travelling. Very common for businesses to set up an "actual address" using a UPS numbered suite as it is considered a physical address unlike a PO Box in a Canadian Post Office. I have one for one of my businesses as well that is a holding company.

I drove by the address in Blaine, Washington a few weeks ago.

Century Mining actually has a 'store front' office that you do not see in the Google Maps Street View. I went in and spoke to the receptionist and asked if there was anyone I could speak with and explained I was just looking for investment information. Apparently no one was available to take the time. I left with a corporate brochure package. The receptionist was polite, professional and somewhat knowledgeable.