I'm doing this all they need is your tax reference code from self employment. Then you do tax returns as normal
But in due course, they will probably run a check and ask you to send in various paperwork relating to your self employment . I had a straightforward compliance type check last year by Concentrix and that related to normal employment. In that case it was easy to prove as I sent in what they requested for the period, e.g. payslips/bank statements/covering letter/proof of hours worked. My concern is that I have now seen elsewhere on other forums (literally since posting this not too long ago) that amongst other things self employed people have been asked to provide and send in;
Copies of adverts
Invoices (which ordinarily have both yours and the customers address)
Clients contact details (!!)
List of clients (!!) and times worked each week
Diary bookings
Bank statements
National insurance small earnings cert
Tax number
My worry is that they contact the customer and ask them to confirm the details on the invoice (breach of privacy for both the customer and me!!). Also, what happens when the customer says that they don't know you and have never had any dealings with you. If you declared yourself as a escort then none of this would actually be a problem, but for the ones who can't or choose not to disclose the true nature of their profession, then all this red tape is a nightmare.