I want to become self-employed and work from home

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Hi,

Thank you all for your answers. I do have a few more questions

Do I have to register my business which to be honest I don't consider it is a business? Should I use my home adress or PO box?
Do I really need an EIN number?
Do I need a business bank account or can I use a regular account to be payed or deposit cheques? (I think it's recommended to have one just to keep personal expenses from business expenses)
Accounting wise, have you hired an accountant that does your taxes? Is there a type of accountant I should kook for?

Thank you