@Charles ********
This is outside the scope of specific Thai Visa/Thai immigration advice, but pertains directly to obtaining a Non-O based on Embassy-certified Affidavit of Income:
In my opinion, you would take that « Déclaration de revenus (pour le visa/permis de séjour en Thaïlande) » that the French Embassy in Bangkok just certified and further do a legalisation of that Déclaration, which, of course, would complete the legalisation at Thailand MFA (Ministry of Foreign Affairs)....
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