A private seller gives you no invoice. That note is yours to write — and it is your only proof.
The purchase date, a description that identifies the piece, the price you paid, and the seller's details. In the Netherlands the opkopersregister expressly asks for a private seller's details; in France the livre de police asks for surname, first name and address, plus the method of payment.
It is the only place that piece's provenance will ever come from again. Without that note you cannot show you bought from someone who could not charge VAT — which is exactly the condition of the margin scheme.
So make a habit of writing the note there and then, with a photo of the piece attached. Asking afterwards, of someone you met once at an antiques market, does not work.
Sources, each checked on 30 August 2026: Royal Decree no. 53 of 23 December 1994 (Belgium), the Dutch government's Digitaal Opkopersregister, the registre d'objets mobiliers on service-public.gouv.fr (France) and gov.uk, VAT margin schemes — Keeping records (UK). Note: VAT Notice 718 is still widely quoted online, but HMRC has withdrawn it.
This is an explanation, not tax or legal advice. Put your own situation to your accountant.
Then applying the margin scheme correctly becomes difficult or impossible. The scheme taxes the difference between purchase and sale; without a purchase price there is no margin to tax and you fall back on the normal rules: VAT on the full selling price. In the UK, HMRC says so in as many words.
From a private individual, from a non-taxable person, from a taxable person who supplied the item exempt because he had no right of deduction, or from another dealer who sold the piece under the margin scheme himself. All four share one feature: there was no deductible VAT on your purchase.
Vintro Pro keeps, per piece, what you paid, when, and where it came from. Your stock list and your margin VAT build themselves while you work.
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