What is the best district to register a marriage in Bangkok with minimal requirements?

Two scenarios you were married outside Thailand and want to register the marriage here or you want to marry here, which one?

If you want to marry here then the procedure is an affidavit from your embassy to say you are free to marry, plus a certified copy of your passport. These docs must be translated and taken to MFA to be legalized. After you get these docs back you go to the ampur to register your marriage. If you want to obtain a non imm O visa based on marriage you need B 400k in a Thai bank account or income letter from your embassy. Each office has it own rules so best talk to your immigration office about their requirements.

No need to show finances for marriage.

Bang Rak amphur is very foreigner friendly for marriage arrangements

This place-- a local amphur. Take an interpreter, who will double as your witness.

Assuming you are married to a Thai national and want that recognised by Thailand then as above the local district office 'amphur' is where to go.

If you where married outside of Thailand they may ask for the marriage certificate to be certified by your embassy and translated into Thai. If you intend to get married here then you will need a letter from your embassy stating you a free to marry.

Amphur office will issue a certificate and Kor ror 2 document which can then be used at immigration to obtain a stay based on marriage. You will have to show 400K baht in a bank account in your name to obtain a 12 month stay

Registering a marriage is not my forte but I believe it’s done at a local amphur office not immigration.