Can I apply for a work permit and extend my visa in Thailand by myself, or must I use an agent?

The individual inquired about the process of applying for a work permit and extending a non-B visa in Thailand. They were informed by their Thai partner that they could not handle the applications themselves and needed to use an agent, who quoted a total fee of 28,000 THB for both services. Respondents advised that the individual could indeed manage the application process independently by visiting the Ministry of Labor for the work permit and the Immigration Office for the visa extension. They suggested gathering the necessary documents, following the process, and indicated that many others have successfully completed these applications without an agent.