But I cant imagine many of those who do things like sell beauty stuff like Avon necessarily are registered.
Companies such as Avon provide HMRC with a list of commissions paid to their agents. Ie names, addresses and amounts.
Sorry but your daughter is committing a criminal offence and potentially so are you, by not reporting it. Your caterer friend will also be committing an offence if she isn’t deducting the necessary NICS etc before paying cash in hand.
We would all like to pay less tax, but the law is the law.
Sorry to be a nag, but it is a criminal offence to get paid cash in hand to avoid paying tax.
I would be going down the route of selling unwanted things on eBay etc and getting a second job, but accepting that legally I have to pay tax on it.