Advice about some VAT scams

Ebay seems to have become a VAT scammer paradise.
VAT means Value Added Tax, and if a sellers turnover for the last rolling 12 months exceeds 61,000, then they must register for VAT.
VAT is a government tax, and VAT registered sellers, MUST pay Customs and Excise 14.89% of the total value of the sale including postage.
There are a few exceptions to the items that are VATable, and any item permantly exported outside the EU is VAT free, but thats not for discussion here
Many many ebay sellers have exceeded this threashold for VAT, yet have failed to register for VAT, this means they are trading illegally and have gained an unfair advantage over legal honest sellers.
The biggest scams though are sellers charging YOU VAT, whilst not being VAT registered, if you look at some listings, they state "price includes VAT @ 17.5%" but is the seller actually VAT registered?
It ios a legal requirement that any VAT registered seller MUST supply on request a fully itemised VAT invoice showing the breakdown of VAT charged, and more importantly the seller VAT registration number.
If your seller claims the price includes VAT, and fails to supply you with an invoice including their VAT number on request, then you have probably been robbed by that seller.
Another whilst legal, but very unethical practice is to charge VAT after the sale, IE you bid, you win, the 17.5% VAT is added to the total amount, unless the seller