Sorry but i think you are wrong.

Without going into too much detail.............inheritance tax is paid where applicable before Probate is issued.

So you saying that we should pay tax twice?

It is really easy for a genuine private seller without a collection to sell 30 items in a tax year.   So no they should not be forced into becoming a Business seller.          Yes i agree a lot of business sellers are trying to fly under the radar.  Saying that its obvious for some of the reasons you state who they are and these are the ones i believe HMRC will target first.