Can just do a marriage visa with multiple re entry's. Need 400k baht in a baht account. 2 months prior to visa. And that's really about it. I used an agent I can recommend and the process was extremely easy.
I don't think they do in their office but they got all my stuff notarized. I just dropped everything off with them. A very short time later I received a hand delivered envelope with everything I needed. They also can advise with agents as well
I don't want to call them visa agents. But they did my marriage Translation stuff. Either they can or know someone who can. Their offices are by all the embassies