Guide chapters
§ - Important Disclaimer Regarding the Nature of the Material00 - How to use the guide01 - First choose the business and responsibility model, then build the marketplace02 - Construction plan: what must exist and when03 - Responsibility Matrix: Operator, Seller, and Suppliers04 - Seller Onboarding: Whom to Allow to Sell05 - Product card: information without which an offer cannot be published06 - GPSR: Product Safety in Practice07 - Product Category Gates08 - Packaging and EPR: who is actually responsible09 - Consumer Law: Sale, Withdrawal, and Complaint10 - Prices, Promotions, Ranking, Advertising, and Reviews11 - Payments, Payouts, VAT, and Sales Documents12 - GDPR without myths: what to record, where, and on what basis13 - DSA: reporting, moderation, and seller traceability14 - P2B: fair rules for business users15 - DAC7: seller data and annual reporting16 - E-commerce accessibility from June 28, 202517 - Cybersecurity and NIS218 - Retention: How long to store data and evidence19 - Post-launch operations: calendar and owners20 - Four business models - specific decisions21 - Document and Procedure Package to Prepare22 - GO / NO-GO Checklist Before Launch23 - Most Common Misconceptions24 - Sources and Update Principle

GO / NO-GO Checklist Before Launch

A 'no' answer to a point marked as blocking will halt public sales.

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QuestionRequired StatusBlocks Start?
Is it known who the seller is for each item and is this visible to the customer everywhere?YESYES
Does the payment flow support the marketplace's designated PSP?YESYES
Do the seller and customer terms and conditions match the actual model?YESYES
Does onboarding establish product roles, import, fulfilment and - only where applicable to the seller - EPR and DAC7?YESYES
Is a trader's offer blocked if GPSR information actually required for the product, e.g., manufacturer, responsible person, identification, or necessary warning, is missing?YESYES
Does each active category have an approved gateway?YESYES
Is there a DSA/GPSR process with deadlines and an owner, and can the public contact use an existing form/email?YESYES
Does the report have a persistent, searchable identifier - e.g., an existing UUID - and retain its status, decision, and communication?YESYES
Can all buyers of a specific product/batch be found?YESYES
Does the checkout display the full price and a clear payment obligation?YESYES
Is the 30-day price calculated from the non-deleted history of offer and variant prices?YES, if promotions existYES
Do withdrawal, complaint, and refund processes function, and is the 14-day period reliably observed, even if manually queued/calendared?YESYES
Are acceptances and consents separated, and can the system reconstruct the person/context, time, and immutable version regardless of the chosen technical structure?YESYES
Are optional cookies blocked until consent is given?YESYES
Does a seller see only their own order data?YESYES
Does DAC7 have an owner, complete data, and a calendar?YES, if the operator is subject to itYES
Does the EPR model distinguish between private/unregistered sales and business sales, and does it establish packaging and fulfillment roles only where applicable?YESYES
Is the full purchase path available, or is there a confirmed micro-enterprise exemption?YESYES for an entity covered by PAD
Has NIS2 self-identification been performed and a timeline established?YES for medium/qualified entitiesYES after the obligation takes effect
Is MFA for administrators and high-risk local operations active, is there a log of PSP account/status changes, and are backups and restore tests performed; and are account/payout changes secured by the PSP if they occur solely with them?YESYES
Are retention periods and the legal hold process known?YESNO, but needs to be fixed before scaling
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