The whole thing is a bit of a mishmash.
The monthly limits are what determines whether it needs to be a business account.
The £43 is an average figure based on the turnover v period.
The money laundering details are to comply with the EU regulations. I suspect they are going to report him to the authorities because they are suspicious about how the account is used and want to get more details. That's an entirely different issue from the personal / business thing.
Bookmarks