On another forum I have read about a man, that wanted to extend his visa based on marriage. This was in December 2012, and he went to Chonburi Immigration in Jomtien.

According to him, Chonburi Immigration told him, that the current requirement for this extension is a monthly income of 43,000 Baht, and since he did not meet the requirement, the female officer told him, she would fix the issue for 10,000 Baht.

So he payed and got the extension.

I just read the Police Order 777-2551, and it says 40,000 Baht per month.

So, - is it 40,000 Baht or 43,000 Baht ?

Personally I have never had any problems when extending my visa, so I am thinking, can this story really be true, or is it pure BS ?

You aren't extending your visa, you are extending your permission to stay, the requirement is 40,000 Baht per month income, or 400,000 Baht in a bank account.

It is 40,000 Baht for an extension of stay for the reason of living with Thai wife.

Yes. 40,000 a month or 400,000 in the bank.