I just went to the post office and told them I needed a po box for my business mailings, they never asked for id so I just set it up

Check to see if they need any company id to open a pobox for a company - all they cared about is how I was going to pay for the rental of the pobox, cash of course. Also when you go to visit the poffice, be sure to look the part, I went wearing dress clothes sounds silly but appearances and first impression to people makes a huge difference also be really casual about it , like you only need it for a few months or something and ask about other options like mail forwarding for example.