As a matter of law you need public liability insurance, that is it. Nothing else.
Your tax that applies depends on how much you make, so its hard to say.
But as a general rule as a sole trader you can earn up to £12,501 tax free.
Starter rate £12,501 to £14,585- 19%
Basic rate£ 14,586 to £25,158 - 20%
Intermediate rate£25,159 to £43,430 - 21%
You need to let HMRC know within 3 months. They will send you a self assessment tax return every year.
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