none. The travel agency did it all for me. I slipped them an extra $20 to keep it painless. I have an ordinary (E-type) visa. You pay $5 extra at the airport or border for it. At a local travel agency they extended it for me for 6 months for about $160, which includes a multiple entry permit so I can leave and come back as much as I want. The time to process this can be 1 to 10 days depending on the backlog. After the 6 months you can extend for another year for $290, and you can do that indefinitely. I believe for a retirement extension you can do it for another year right away
I have an ordinary (E-type) visa. You pay $5 extra at the airport or border for it. At a local travel agency they extended it for me for 6 months for about $160, which includes a multiple entry permit so I can leave and come back as much as I want. The time to process this can be 1 to 10 days depending on the backlog. After the 6 months you can extend for another year for $290, and you can do that indefinitely. I believe for a retirement extension you can do it for another year right away
First time doing business in Thailand I see. Best to fill it with concrete and build something new. Almost certainly will cost you more to try to fix the skeleton