If you are applying from the UK via the Royal Thai Embassy. You need to use their Official online portal. There is no need for a Police check and don't ask for it on their portal. You do need the following if applying for a multi entry Non O: Scanned copy of your passport. 2 passport size photos, one bank statement no older than 3 months old with a balance of more than 10k. Scanned copy of your wife's Thai ID and a scanned copy of the marriage certificate. When scanning you need to save in a JPEG format and NOT PDF. If you apply on a Sunday you will have your visa back accepted in under 10 working days. You need to send the photo copies of the scans including the two passport photos. Don't send your original passport. Also included a stamped address envelope. It's a very easy process and the Royal Thai Embassy team are outstanding. Good luck.
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