Self-assessment advice request

Hi, posting as a last resort as I can't seem to get hold of anyone through the helpline or online chat - hope someone can help! I'm an external examiner in my spare time for UK universities and have earned over the £1,000 limit, so this is my first year submitting a self-assessment. I have what are hopefully easy questions please... thank you for any help! 1) The registration process needs a business address which will be listed publicly. Am I allowed to use a PO Box so I don't have to post my home address online? I've also read about potentially using an accountant who can use their address, though that seems a bit expensive given my very minor earnings, and it's not clear from reading online whether this is allowed or what any downsides may be. 2) Similarly, I have to give a phone number and contact email for the "business" - will these be made public too? Thank you again :)

Hi,
I can confirm that HMRC do not publish details of Self Assessment Registration online. If you are setting up a limited company you would need to contact Companies House regarding their registration process. 
Thank you.

Thanks so much! I spoke to someone over Twitter at the weekend who was super helpful and they also let me know - appreciate the confirmation 😊