Is it straightforward to change from a retirement extension to a marriage extension in Thailand?

Nasty part of application for Extension of Stay. Every year same documents different pictures.

You may need to write a letter on why you want to change the reason for your extension.

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@Rob***

, said you're gonna need a photos of you and your wife standing in front of the address numbers of your house, a couple of you from the wedding, and a couple of you two casually sitting around the house, a hand drawn map to your house. Sometimes copies of your freedom of affirmation to marry, the original marriage certificate (with the rose borders), an updated Kor Ror 2 (showing you're still married).

Plus it takes two trips to the immigration office to pull off because of the 30 day under consideration period, AND at some immigration offices they come to your house for an in home interview during the 30 day period to make sure you're really married

You need a few more copies and pictures, less money in the bank or monthly income and you get a 1 month under consideration first before the total year. But yeah it is straight forward.