Interest in a savings account might be 0.5% at best. In a Fixed Deposit Account at Bangkok Bank maybe 1.85% for a 7 months term which is slightly better than a 12 months term. Strange but true. Ask me how I know.
Correct,thats why I said some. There are 44 countries just in Europe with embassies and consulates in Thailand. Not every country has a totally useless embassy like the US which has almost stopped issuing any type of certificate for US citizens.
We're talking about for example travel agents for heavens sake. They are everywhere in Bangkok and in other major cities. In what neighborhood are you located?
Then I guess you need to certify/legalize a passport copy back home or maybe in a neighboring country where there is an embassy or consulate.The MFA won't probably accept this to be done by anyone. Same with the marriage license.