Do it yourself. Take two passport photos a letter from your bank and your bank book caught up to that day. I always did a small transaction that day then caught it up go to immigration and the forms are not that difficult. I go to Sakon Nakhon and they are very helpful.
October of 2023 I did my 90 day check in in February and they gave me the 1 year extension I left the country and got a re entry stamp and am returning in December. Got the Visa while in the US originally.