Put the four countries side by side and a hard core remains.
Its own number, the purchase date, the purchase price, who sold it to you, a description of the piece, and later the sale date and selling price. That is the core that returns in all four countries. On top of it each country asks its own: the UK wants purchase and sale on the same row, France wants the method of payment.
Anyone active in two of the four countries is better off keeping the strictest version from the start. Adding data to pieces you have already sold is no longer possible — and with unique pieces there is no second example to derive it from.
The striking thing about the British list is its shape: HMRC wants purchase and sale on the same line, margin and VAT due included. That is exactly what the Belgian comparison register does by hand.
purchases, sales, and a comparison register linking the two
date, description, cost price — plus the details of a private seller
nature, characteristics, origin, method of payment, seller's name and address
stock number, purchase and sale, the margin and the VAT — one sixth
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 Note: VAT Notice 718 is still widely quoted online, but HMRC has withdrawn it.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.
Yes, and it does not have to mean anything. For series an article number needs meaning, because it stands for a kind. For unique pieces it stands for exactly that one piece, so a running series does the job. What does matter: the same number appears on the label, in your list and with your photo.
In the Netherlands anyone trading professionally in second-hand goods must register and keep an opkopersregister — nowadays digital, the DOR. In France it is the registre d'objets mobiliers, colloquially the livre de police. Neither is about VAT: both target handling stolen goods. In Belgium it runs through the VAT registers of the margin scheme.
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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